Android之一种很有趣的界面跳动提示动画

上一个效果图：

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先上布局：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <RelativeLayout
        android:id="@+id/red"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="#ff0000" >

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_above="@+id/switch2blue"
            android:layout_centerHorizontal="true"
            android:text="首页" />

        <Button
            android:id="@+id/switch2blue"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerInParent="true"
            android:text="置换位蓝色" />
    </RelativeLayout>

    <RelativeLayout
        android:id="@+id/blue"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="#0000ff" >

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_above="@+id/switch2red"
            android:layout_centerHorizontal="true"
            android:text="第二页" />

        <Button
            android:id="@+id/switch2red"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentBottom="true"
            android:layout_centerHorizontal="true"
            android:text="置换位红色" />
    </RelativeLayout>

</RelativeLayout>

代码：

import java.lang.reflect.Field;
import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.util.DisplayMetrics;
import android.view.GestureDetector;
import android.view.MotionEvent;
import android.view.View;
import android.view.GestureDetector.OnGestureListener;
import android.view.View.OnClickListener;
import android.view.View.OnTouchListener;
import android.view.animation.AccelerateDecelerateInterpolator;
import android.view.animation.AccelerateInterpolator;
import android.view.animation.Animation;
import android.view.animation.AnimationSet;
import android.view.animation.TranslateAnimation;
import android.view.animation.Animation.AnimationListener;
import android.widget.Button;
import android.widget.RelativeLayout;

public class MainActivity extends Activity implements OnClickListener,
        OnTouchListener, OnGestureListener {

    private RelativeLayout red, blue;
    private Button switch2blue, switch2red;

    private float thisDelta = 0.05f;
    private static boolean hasEverPulled = false;
    private boolean pulled = false;
    private static int height;
    private GestureDetector gestureDetector;
    private static int statusHeight = 0;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        DisplayMetrics metrics = getResources().getDisplayMetrics();
        height = metrics.heightPixels;

        statusHeight = getStatusHeight();

        initView();

        // 跳动提示可以上拉
        final Handler handler = new Handler();
        handler.postDelayed(new Runnable() {

            @Override
            public void run() {
                jump(thisDelta);
                // handler.postDelayed(this, 3000);
            }
        }, 3000);

    }

    private void initView() {
        red = (RelativeLayout) findViewById(R.id.red);
        blue = (RelativeLayout) findViewById(R.id.blue);

        switch2blue = (Button) findViewById(R.id.switch2blue);
        switch2red = (Button) findViewById(R.id.switch2red);

        switch2blue.setOnClickListener(this);
        switch2red.setOnClickListener(this);
        blue.setOnTouchListener(this);
        blue.setLongClickable(true);
        gestureDetector = new GestureDetector(this, this);
    }

    @Override
    public void onClick(View arg0) {
        // TODO Auto-generated method stub
        switch (arg0.getId()) {
        case R.id.switch2blue:

            red2BlueUI();
            break;

        case R.id.switch2red:
            blue2RedUI();
            break;
        }
    }

    // 从红页面转到蓝页面
    private void red2BlueUI() {
        blue.bringToFront();
        blue.requestLayout();
        blue.invalidate();
    }

    // 从蓝页面转到红页面
    private void blue2RedUI() {
        red.bringToFront();
        red.requestLayout();
        red.invalidate();
    }

    // 获取状态栏的高度
    private int getStatusHeight() {
        Class<?> c = null;
        Object obj = null;
        Field field = null;
        int x = 0;
        int height = 0;
        try {
            c = Class.forName("com.android.internal.R$dimen");
            obj = c.newInstance();
            field = c.getField("status_bar_height");
            x = Integer.parseInt(field.get(obj).toString());
            height = getResources().getDimensionPixelSize(x);
        } catch (Exception e) {
            e.printStackTrace();
        }

        return height;
    }

    // 主页面跳动
    private void jump(float delta) {
        if (thisDelta - 0.03f < 0.001f) {
            thisDelta = 0.05f;
            return;
        }
        thisDelta = delta;

        if (hasEverPulled) {
            return;
        }
        playJumpAnimation(thisDelta);
    }

    // 上拉/下拉主页面
    private void pull(boolean upward) {
        if (upward && pulled) {
            return;
        }
        if (!upward && !pulled) {
            return;
        }

        float originalY;
        float finalY;
        if (!pulled) {
            originalY = 0;
            finalY = (float) (0 - height + 0.4 * height);
        } else {
            originalY = (float) (0 - height + 0.4 * height);
            finalY = 0;
        }
        pulled = !pulled;

        AnimationSet animationSet = new AnimationSet(true);
        animationSet.addAnimation(new TranslateAnimation(0, 0, originalY,
                finalY));

        animationSet.setDuration(300);
        animationSet.setInterpolator(new AccelerateDecelerateInterpolator());
        animationSet.setFillAfter(true);

        animationSet.setAnimationListener(new AnimationListener() {

            @Override
            public void onAnimationStart(Animation animation) {
                if (!pulled) {
                    red2BlueUI();
                }
            }

            @Override
            public void onAnimationRepeat(Animation animation) {

            }

            @Override
            public void onAnimationEnd(Animation animation) {
                // if (pulled) {
                // blue2RedUI();
                // }
            }
        });

        blue.startAnimation(animationSet);

        hasEverPulled = true;
    }

    // 跳起动画
    private void playJumpAnimation(final float delta) {
        float originalY = 0;
        float finalY = 0 - height * delta;
        AnimationSet animationSet = new AnimationSet(true);
        animationSet.addAnimation(new TranslateAnimation(0, 0, originalY,
                finalY));

        animationSet.setDuration(300);
        animationSet.setInterpolator(new AccelerateDecelerateInterpolator());
        animationSet.setFillAfter(true);

        animationSet.setAnimationListener(new AnimationListener() {

            @Override
            public void onAnimationStart(Animation animation) {
            }

            @Override
            public void onAnimationRepeat(Animation animation) {
            }

            @Override
            public void onAnimationEnd(Animation animation) {
                playLandAnimation(delta);
            }
        });

        blue.startAnimation(animationSet);
    }

    // 落下动画
    private void playLandAnimation(final float delta) {
        float originalY = 0 - height * delta;
        float finalY = 0;
        AnimationSet animationSet = new AnimationSet(true);
        animationSet.addAnimation(new TranslateAnimation(0, 0, originalY,
                finalY));

        animationSet.setDuration(200);
        animationSet.setInterpolator(new AccelerateInterpolator());
        animationSet.setFillAfter(true);

        animationSet.setAnimationListener(new AnimationListener() {

            @Override
            public void onAnimationStart(Animation animation) {
            }

            @Override
            public void onAnimationRepeat(Animation animation) {
            }

            @Override
            public void onAnimationEnd(Animation animation) {
                jump(0.03f);
            }
        });

        blue.startAnimation(animationSet);
    }

    @Override
    public boolean onDown(MotionEvent e) {
        pull(false);

        return false;
    }

    @Override
    public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
            float velocityY) {
        // 手势滑动达到100才触发
        if (e1.getY() - e2.getY() > 100) {
            pull(true);
        } else if (e2.getY() >= e1.getY()) {
            pull(false);
        }

        return false;
    }

    @Override
    public void onLongPress(MotionEvent e) {
    }

    @Override
    public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX,
            float distanceY) {
        return false;
    }

    @Override
    public void onShowPress(MotionEvent e) {
    }

    @Override
    public boolean onSingleTapUp(MotionEvent e) {
        return false;
    }

    @Override
    public boolean onTouch(View v, MotionEvent event) {
        if (pulled) {
            // 首张页可触控点
            if (event.getY() > height * 0.4 - statusHeight) {
                return false;
            }
        }

        return gestureDetector.onTouchEvent(event);
    }
}