学步园

首先打开”main.xml”布局文件

，添加TextView命名为tvHelloWorld：保存。

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<TextView
	android:id="@+id/tvHelloWorld" 
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="@string/hello"
    />
</LinearLayout>

这时候Eclipse编译器会自动生成TextView代码,打开R.java文件

可以看到

/* AUTO-GENERATED FILE.  DO NOT MODIFY.
 *
 * This class was automatically generated by the
 * aapt tool from the resource data it found.  It
 * should not be modified by hand.
 */

package idroidgame.ActivityTest;

public final class R {
    public static final class attr {
    }
    public static final class drawable {
        public static final int icon=0x7f020000;
    }
    public static final class id {
        public static final int tvHelloWorld=0x7f050000;
    }
    public static final class layout {
        public static final int main=0x7f030000;
    }
    public static final class string {
        public static final int app_name=0x7f040001;
        public static final int hello=0x7f040000;
    }
}

然后在ActivityText.java中输入

package idroidgame.ActivityTest;

import android.app.Activity;
import android.os.Bundle;

import android.widget.TextView;
public class ActivityTest extends Activity {
	TextView tv=null;
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        tv=(TextView)this.findViewById(R.id.tvHelloWorld);
        String str="设置TextView的值";
        tv.setText(str);
    }
    
}

TextView的setText有很多重载方法；