Android项目实战（五）：TextView自适应大小

对于设置TextView的字体默认大小对于UI界面的好看程度是很重要的，小屏幕设置的文字过大或者大屏幕设置的文字过小都造成UI的不美观

现在就让我们学习自适应大小的TextView控件，即当文字长度变化时，文字的大小会相应的变化，保证显示在一行当中

实现依靠于第三方类库

第三方类来源：

https://github.com/grantland/android-autofittextview

和正常的使用TextView一样，只需要将要自适应的TextView标签设置为<me.grantland.widget.AutofitTextView/>

注意：一定要设置为单行，否定无法显示效果

android:singleLine="true"

 <me.grantland.widget.AutofitTextView
             android:id="@+id/output_autofit"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:text="@string/example"
             android:textSize="50sp"
             android:gravity="center"
             android:singleLine="true"
             autofit:minTextSize="8sp"
             />

布局文件：

 <?xml version="1.0" encoding="utf-8"?>
 <ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
             xmlns:autofit="http://schemas.android.com/apk/res-auto"
     android:layout_width="match_parent"
     android:layout_height="match_parent">
     <LinearLayout
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:orientation="vertical"
         >
         <EditText
             android:id="@+id/input"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:singleLine="true"
             android:hint="@string/input_hint"
             android:text="@string/example"/>
         <TextView
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:text="@string/label_normal"
             />
         <TextView
             android:id="@+id/output"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:text="@string/example"
             android:textSize="50sp"
             android:gravity="center"
             />
         <TextView
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:text="@string/label_autofit"
             />
         <me.grantland.widget.AutofitTextView
             android:id="@+id/output_autofit"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:text="@string/example"
             android:textSize="50sp"
             android:gravity="center"
             android:singleLine="true"
             autofit:minTextSize="8sp"
             />
     </LinearLayout>
 </ScrollView>

activity_main.xml

string.xml

 <?xml version="1.0" encoding="utf-8"?>
 <resources>
 
     <string name="app_name">Texttest</string>
     <string name="action_settings">Settings</string>
     <string name="hello_world">Hello world!</string>
 
     <string name="input_hint">text</string>
     <string name="label_normal">Normal:</string>
     <string name="label_autofit">Autofit:</string>
 
     <string name="example">This is an example</string>
 
 </resources>

activity

 package com.example.texttest;
 
 import android.app.Activity;
 import android.os.Bundle;
 import android.text.Editable;
 import android.text.TextWatcher;
 import android.view.Menu;
 import android.widget.EditText;
 import android.widget.TextView;
 
 public class MainActivity extends Activity {
 
     private TextView mOutput;
     private TextView mAutofitOutput;
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
         mOutput = (TextView)findViewById(R.id.output);
         mAutofitOutput = (TextView)findViewById(R.id.output_autofit);
 
         ((EditText)findViewById(R.id.input)).addTextChangedListener(new TextWatcher() {
             @Override
             public void beforeTextChanged(CharSequence charSequence, int i, int i2, int i3) {
                 // do nothing
             }
 
             @Override
             public void onTextChanged(CharSequence charSequence, int i, int i2, int i3) {
                 mOutput.setText(charSequence);
                 mAutofitOutput.setText(charSequence);
             }
 
             @Override
             public void afterTextChanged(Editable editable) {
                 // do nothing
             }
         });
     }
 
     @Override
     public boolean onCreateOptionsMenu(Menu menu) {
         // Inflate the menu; this adds items to the action bar if it is present.
         getMenuInflater().inflate(R.menu.main, menu);
         return true;
     }
 
 }

MainActivity.java

效果：