Android仿微信界面

效果图

原理介绍

1、先绘制一个颜色（例如：粉红）

2、设置Mode=DST_IN

3、绘制我们这个可爱的小机器人

回答我，显示什么，是不是显示交集，交集是什么？交集是我们的小机器人的非透明区域，也就是那张脸，除了两个眼；

好了，那怎么变色呢？

我绘制一个颜色的时候，难道不能设置alpha么

自定义图标控件

自定义属性

<?xml version="1.0" encoding="utf-8"?>

<resources>  

    <attr name="icon" format="reference" />

    <attr name="color" format="color" />

    <attr name="text" format="string" />

    <attr name="text_size" format="dimension" />  

    <declare-styleable name="ChangeColorIconView">

        <attr name="icon" />

        <attr name="color" />

        <attr name="text" />

        <attr name="text_size" />

    </declare-styleable>  

</resources>

绘制图标

绘制图标有很多步骤呀，我来列一列

1、计算alpha（默认为0）

2、绘制原图

3、在绘图区域，绘制一个纯色块（设置了alpha），此步绘制在内存的bitmap上

4、设置mode，针对内存中的bitmap上的paint

5、绘制我们的图标，此步绘制在内存的bitmap上

6、绘制原文本

7、绘制设置alpha和颜色后的文本

8、将内存中的bitmap绘制出来

根据上面的步骤，可以看出来，我们的图标其实绘制了两次，为什么要绘制原图呢，因为我觉得比较好看。

3-5步骤，就是我们上面分析的原理

6-7步，是绘制文本，可以看到，我们的文本就是通过设置alpha实现的

package com.zhy.weixin6.ui;

import android.content.Context;

import android.content.res.TypedArray;

import android.graphics.Bitmap;

import android.graphics.Bitmap.Config;

import android.graphics.BitmapFactory;

import android.graphics.Canvas;

import android.graphics.Paint;

import android.graphics.PorterDuff;

import android.graphics.PorterDuffXfermode;

import android.graphics.Rect;

import android.graphics.drawable.BitmapDrawable;

import android.os.Bundle;

import android.os.Looper;

import android.os.Parcelable;

import android.util.AttributeSet;

import android.util.Log;

import android.util.TypedValue;

import android.view.View;

public class ChangeColorIconWithTextView extends View

{

    private Bitmap mBitmap;

    private Canvas mCanvas;

    private Paint mPaint;

    /**

     * 颜色

     */

    private int mColor = 0xFF45C01A;

    /**

     * 透明度 0.0-1.0

     */

    private float mAlpha = 0f;

    /**

     * 图标

     */

    private Bitmap mIconBitmap;

    /**

     * 限制绘制icon的范围

     */

    private Rect mIconRect;

    /**

     * icon底部文本

     */

    private String mText = "微信";

    private int mTextSize = (int) TypedValue.applyDimension(

            TypedValue.COMPLEX_UNIT_SP, 10, getResources().getDisplayMetrics());

    private Paint mTextPaint;

    private Rect mTextBound = new Rect();

    public ChangeColorIconWithTextView(Context context)

    {

        super(context);

    }

    /**

     * 初始化自定义属性值

     *

     * @param context

     * @param attrs

     */

    public ChangeColorIconWithTextView(Context context, AttributeSet attrs)

    {

        super(context, attrs);

        // 获取设置的图标

        TypedArray a = context.obtainStyledAttributes(attrs,

                R.styleable.ChangeColorIconView);

        int n = a.getIndexCount();

        for (int i = 0; i < n; i++)

        {

            int attr = a.getIndex(i);

            switch (attr)

            {

            case R.styleable.ChangeColorIconView_icon:

                BitmapDrawable drawable = (BitmapDrawable) a.getDrawable(attr);

                mIconBitmap = drawable.getBitmap();

                break;

            case R.styleable.ChangeColorIconView_color:

                mColor = a.getColor(attr, 0x45C01A);

                break;

            case R.styleable.ChangeColorIconView_text:

                mText = a.getString(attr);

                break;

            case R.styleable.ChangeColorIconView_text_size:

                mTextSize = (int) a.getDimension(attr, TypedValue

                        .applyDimension(TypedValue.COMPLEX_UNIT_SP, 10,

                                getResources().getDisplayMetrics()));

                break;

            }

        }

        a.recycle();

        mTextPaint = new Paint();

        mTextPaint.setTextSize(mTextSize);

        mTextPaint.setColor(0xff555555);

        // 得到text绘制范围

        mTextPaint.getTextBounds(mText, 0, mText.length(), mTextBound);

    }

    @Override

    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec)

    {

        super.onMeasure(widthMeasureSpec, heightMeasureSpec);

        // 得到绘制icon的宽

        int bitmapWidth = Math.min(getMeasuredWidth() - getPaddingLeft()

                - getPaddingRight(), getMeasuredHeight() - getPaddingTop()

                - getPaddingBottom() - mTextBound.height());

        int left = getMeasuredWidth() / 2 - bitmapWidth / 2;

        int top = (getMeasuredHeight() - mTextBound.height()) / 2 - bitmapWidth

                / 2;

        // 设置icon的绘制范围

        mIconRect = new Rect(left, top, left + bitmapWidth, top + bitmapWidth);

    }

    @Override

    protected void onDraw(Canvas canvas)

    {

        int alpha = (int) Math.ceil((255 * mAlpha));

        canvas.drawBitmap(mIconBitmap, null, mIconRect, null);

        setupTargetBitmap(alpha);

        drawSourceText(canvas, alpha);

        drawTargetText(canvas, alpha);

        canvas.drawBitmap(mBitmap, 0, 0, null);

    }

    private void setupTargetBitmap(int alpha)

    {

        mBitmap = Bitmap.createBitmap(getMeasuredWidth(), getMeasuredHeight(),

                Config.ARGB_8888);

        mCanvas = new Canvas(mBitmap);

        mPaint = new Paint();

        mPaint.setColor(mColor);

        mPaint.setAntiAlias(true);

        mPaint.setDither(true);

        mPaint.setAlpha(alpha);

        mCanvas.drawRect(mIconRect, mPaint);

        mPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_IN));

        mPaint.setAlpha(255);

        mCanvas.drawBitmap(mIconBitmap, null, mIconRect, mPaint);

    }

    private void drawSourceText(Canvas canvas, int alpha)

    {

        mTextPaint.setTextSize(mTextSize);

        mTextPaint.setColor(0xff333333);

        mTextPaint.setAlpha(255 - alpha);

        canvas.drawText(mText, mIconRect.left + mIconRect.width() / 2

                - mTextBound.width() / 2,

                mIconRect.bottom + mTextBound.height(), mTextPaint);

    }

    private void drawTargetText(Canvas canvas, int alpha)

    {

        mTextPaint.setColor(mColor);

        mTextPaint.setAlpha(alpha);

        canvas.drawText(mText, mIconRect.left + mIconRect.width() / 2

                - mTextBound.width() / 2,

                mIconRect.bottom + mTextBound.height(), mTextPaint);

    }

    public void setIconAlpha(float alpha)

    {

        this.mAlpha = alpha;

        invalidateView();

    }

    private void invalidateView()

    {

        if (Looper.getMainLooper() == Looper.myLooper())

        {

            invalidate();

        } else

        {

            postInvalidate();

        }

    }

    public void setIconColor(int color)

    {

        mColor = color;

    }

    public void setIcon(int resId)

    {

        this.mIconBitmap = BitmapFactory.decodeResource(getResources(), resId);

        if (mIconRect != null)

            invalidateView();

    }

    public void setIcon(Bitmap iconBitmap)

    {

        this.mIconBitmap = iconBitmap;

        if (mIconRect != null)

            invalidateView();

    }

    private static final String INSTANCE_STATE = "instance_state";

    private static final String STATE_ALPHA = "state_alpha";

    @Override

    protected Parcelable onSaveInstanceState()

    {

        Bundle bundle = new Bundle();

        bundle.putParcelable(INSTANCE_STATE, super.onSaveInstanceState());

        bundle.putFloat(STATE_ALPHA, mAlpha);

        return bundle;

    }

    @Override

    protected void onRestoreInstanceState(Parcelable state)

    {

        if (state instanceof Bundle)

        {

            Bundle bundle = (Bundle) state;

            mAlpha = bundle.getFloat(STATE_ALPHA);

            super.onRestoreInstanceState(bundle.getParcelable(INSTANCE_STATE));

        } else

        {

            super.onRestoreInstanceState(state);

        }

    }

}

MainActivity

package com.zhy.weixin6.ui;

import java.lang.reflect.Field;

import java.lang.reflect.Method;

import java.util.ArrayList;

import java.util.List;

import android.annotation.SuppressLint;

import android.os.Bundle;

import android.support.v4.app.Fragment;

import android.support.v4.app.FragmentActivity;

import android.support.v4.app.FragmentPagerAdapter;

import android.support.v4.view.ViewPager;

import android.support.v4.view.ViewPager.OnPageChangeListener;

import android.view.Menu;

import android.view.MenuItem;

import android.view.View;

import android.view.View.OnClickListener;

import android.view.ViewConfiguration;

import android.view.Window;

import android.widget.SearchView;

import android.widget.Toast;

@SuppressLint("NewApi")

public class MainActivity extends FragmentActivity implements

        OnPageChangeListener, OnClickListener

{

    private ViewPager mViewPager;

    private List<Fragment> mTabs = new ArrayList<Fragment>();

    private FragmentPagerAdapter mAdapter;

    private String[] mTitles = new String[] { "First Fragment!",

            "Second Fragment!", "Third Fragment!", "Fourth Fragment!" };

    private List<ChangeColorIconWithTextView> mTabIndicator = new ArrayList<ChangeColorIconWithTextView>();

    @Override

    protected void onCreate(Bundle savedInstanceState)

    {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        setOverflowShowingAlways();

        getActionBar().setDisplayShowHomeEnabled(false);

        mViewPager = (ViewPager) findViewById(R.id.id_viewpager);

        initDatas();

        mViewPager.setAdapter(mAdapter);

        mViewPager.setOnPageChangeListener(this);

    }

    private void initDatas()

    {

        for (String title : mTitles)

        {

            TabFragment tabFragment = new TabFragment();

            Bundle args = new Bundle();

            args.putString("title", title);

            tabFragment.setArguments(args);

            mTabs.add(tabFragment);

        }

        mAdapter = new FragmentPagerAdapter(getSupportFragmentManager())

        {

            @Override

            public int getCount()

            {

                return mTabs.size();

            }

            @Override

            public Fragment getItem(int arg0)

            {

                return mTabs.get(arg0);

            }

        };

        initTabIndicator();

    }

     SearchView searchView;

    @Override

    public boolean onCreateOptionsMenu(Menu menu)

    {

        getMenuInflater().inflate(R.menu.main, menu);

        MenuItem searchItem = menu.findItem(R.id.action_search);

         searchView = (SearchView) searchItem.getActionView();  

        return true;

    }

    @Override

    public boolean onSearchRequested() {

        // TODO Auto-generated method stub

        Toast.makeText(getApplicationContext(), searchView.getQuery(), 0).show();

        return super.onSearchRequested();

    }

    private void initTabIndicator()

    {

        ChangeColorIconWithTextView one = (ChangeColorIconWithTextView) findViewById(R.id.id_indicator_one);

        ChangeColorIconWithTextView two = (ChangeColorIconWithTextView) findViewById(R.id.id_indicator_two);

        ChangeColorIconWithTextView three = (ChangeColorIconWithTextView) findViewById(R.id.id_indicator_three);

        ChangeColorIconWithTextView four = (ChangeColorIconWithTextView) findViewById(R.id.id_indicator_four);

        mTabIndicator.add(one);

        mTabIndicator.add(two);

        mTabIndicator.add(three);

        mTabIndicator.add(four);

        one.setOnClickListener(this);

        two.setOnClickListener(this);

        three.setOnClickListener(this);

        four.setOnClickListener(this);

        one.setIconAlpha(1.0f);

    }

    @Override

    public void onPageSelected(int arg0)

    {

    }

    @Override

    public void onPageScrolled(int position, float positionOffset,

            int positionOffsetPixels)

    {

        // Log.e("TAG", "position = " + position + " , positionOffset = "

        // + positionOffset);

        if (positionOffset > 0)

        {

            ChangeColorIconWithTextView left = mTabIndicator.get(position);

            ChangeColorIconWithTextView right = mTabIndicator.get(position + 1);

            left.setIconAlpha(1 - positionOffset);

            right.setIconAlpha(positionOffset);

        }

    }

    @Override

    public void onPageScrollStateChanged(int state)

    {

    }

    @Override

    public void onClick(View v)

    {

        resetOtherTabs();

        switch (v.getId())

        {

        case R.id.id_indicator_one:

            mTabIndicator.get(0).setIconAlpha(1.0f);

            mViewPager.setCurrentItem(0, false);

            break;

        case R.id.id_indicator_two:

            mTabIndicator.get(1).setIconAlpha(1.0f);

            mViewPager.setCurrentItem(1, false);

            break;

        case R.id.id_indicator_three:

            mTabIndicator.get(2).setIconAlpha(1.0f);

            mViewPager.setCurrentItem(2, false);

            break;

        case R.id.id_indicator_four:

            mTabIndicator.get(3).setIconAlpha(1.0f);

            mViewPager.setCurrentItem(3, false);

            break;

        }

    }

    /**

     * 重置其他的Tab

     */

    private void resetOtherTabs()

    {

        for (int i = 0; i < mTabIndicator.size(); i++)

        {

            mTabIndicator.get(i).setIconAlpha(0);

        }

    }

    @Override

    public boolean onMenuOpened(int featureId, Menu menu)

    {

        if (featureId == Window.FEATURE_ACTION_BAR && menu != null)

        {

            if (menu.getClass().getSimpleName().equals("MenuBuilder"))

            {

                try

                {

                    Method m = menu.getClass().getDeclaredMethod(

                            "setOptionalIconsVisible", Boolean.TYPE);

                    m.setAccessible(true);

                    m.invoke(menu, true);

                } catch (Exception e)

                {

                }

            }

        }

        return super.onMenuOpened(featureId, menu);

    }

    private void setOverflowShowingAlways()

    {

        try

        {

            // true if a permanent menu key is present, false otherwise.

            ViewConfiguration config = ViewConfiguration.get(this);

            Field menuKeyField = ViewConfiguration.class

                    .getDeclaredField("sHasPermanentMenuKey");

            menuKeyField.setAccessible(true);

            menuKeyField.setBoolean(config, false);

        } catch (Exception e)

        {

            e.printStackTrace();

        }

    }

}

Activity里面代码虽然没什么注释，但是很简单哈，就是初始化Fragment，得到我们的适配器，然后设置给ViewPager；

initTabIndicator我们初始化我们的自定义控件，以及加上了点击事件；

唯一一个需要指出的就是：

我们在onPageScrolled中，动态的获取position以及positionOffset，然后拿到左右两个View，设置positionOffset ；

两个反射的方法，是控制Actionbar的图标的，和点击menu按键显示的

TabFragment

package com.zhy.weixin6.ui;  

import android.graphics.Color;

import android.os.Bundle;

import android.support.v4.app.Fragment;

import android.view.Gravity;

import android.view.LayoutInflater;

import android.view.View;

import android.view.ViewGroup;

import android.widget.TextView;  

public class TabFragment extends Fragment

{

    private String mTitle = "Default";  

    public TabFragment()

    {

    }  

    @Override

    public View onCreateView(LayoutInflater inflater, ViewGroup container,

            Bundle savedInstanceState)

    {

        if (getArguments() != null)

        {

            mTitle = getArguments().getString("title");

        }  

        TextView textView = new TextView(getActivity());

        textView.setTextSize(20);

        textView.setBackgroundColor(Color.parseColor("#ffffffff"));

        textView.setGravity(Gravity.CENTER);

        textView.setText(mTitle);

        return textView;

    }

}

menu.xml文件

<menu xmlns:android="http://schemas.android.com/apk/res/android" >

    <item

        android:id="@+id/action_search"

        android:actionViewClass="android.widget.SearchView"

        android:icon="@drawable/actionbar_search_icon"

        android:showAsAction="ifRoom|collapseActionView"

        android:title="@string/action_search"/>

    <item

        android:id="@+id/action_group_chat"

        android:icon="@drawable/ofm_group_chat_icon"

        android:title="@string/action_group_chat"/>

    <item

        android:id="@+id/action_add_friend"

        android:icon="@drawable/ofm_add_icon"

        android:title="@string/action_add_friend"/>

    <item

        android:id="@+id/action_scan"

        android:icon="@drawable/ofm_qrcode_icon"

        android:title="@string/action_scan"/>

    <item

        android:id="@+id/action_feed"

        android:icon="@drawable/ofm_feedback_icon"

        android:title="@string/action_feed"/>

</menu>

源码下载

参考链接

Android 高仿微信6.0主界面带你玩转切换图标变色 - Hongyang - 博客频道 - CSDN.NET

http://blog.csdn.net/lmj623565791/article/details/41087219