Android组件之SeekBar_android 继承 seekbar 组件-优快云博客

本文介绍了一个简单的Android应用示例，该应用使用SeekBar组件并实现了SeekBar的监听器接口，以实时更新进度并显示在TextView上。此外，当SeekBar停止触摸时会弹出提示框显示最终进度。

新建一个Activity

package cn.z.view;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.widget.LinearLayout;
import android.widget.SeekBar;
import android.widget.SeekBar.OnSeekBarChangeListener;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends Activity implements OnSeekBarChangeListener {
	private SeekBar seekbar;
	private TextView tv;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		seekbar = (SeekBar)findViewById(R.id.seekbar);
		tv = (TextView)findViewById(R.id.tv);
		seekbar.setOnSeekBarChangeListener(this);

	}

	@Override
	public void onProgressChanged(SeekBar arg0, int arg1, boolean arg2) {
		// TODO Auto-generated method stub
		tv.setText(""+arg1);
	}

	@Override
	public void onStartTrackingTouch(SeekBar arg0) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void onStopTrackingTouch(SeekBar arg0) {
		// TODO Auto-generated method stub
		Toast.makeText(this,""+arg0.getProgress(),0).show();
	}
}

XML文件内容：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >
    
    <SeekBar 
        android:id="@+id/seekbar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        />
    <TextView 
        android:id="@+id/tv"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:textSize="25sp"
        android:gravity="center"
        />

</LinearLayout>