步步为营_Android开发课[27]_用户界面之SeekBar(拖动条)

Focus on technology, enjoy life！—— QQ：804212028
浏览链接：http://blog.csdn.net/y18334702058/article/details/44624305

• 主题：用户界面之SeekBar(拖动条)
  -

SeekBar拖动条（实例）：

activity_main.xml:

<?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" 
    > 
        <SeekBar        
            android:id="@+id/seek" 
            android:layout_width="fill_parent" 
            android:layout_height="wrap_content" 
            android:max="100" 
            android:progress="50" 
        /> 

        <TextView 
            android:id="@+id/progress" 
            android:layout_width="fill_parent" 
            android:layout_height="wrap_content" 
        /> 

        <TextView  
            android:id="@+id/tracking" 
            android:layout_width="fill_parent" 
            android:layout_height="wrap_content" 
        /> 
</LinearLayout>

MainActivity.java:

import android.app.Activity;
import android.os.Bundle;
import android.widget.SeekBar;
import android.widget.SeekBar.OnSeekBarChangeListener;
import android.widget.TextView;

public class MainActivity extends Activity {

        SeekBar mSeekBar;
        TextView mProgressText;
        TextView mTrackingText;

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

                //取得SeekBar对象
                mSeekBar = (SeekBar) findViewById(R.id.seek);
                mSeekBar.setOnSeekBarChangeListener(new Listener());
                mProgressText = (TextView) findViewById(R.id.progress);
                mTrackingText = (TextView) findViewById(R.id.tracking);
        }

     class Listener implements OnSeekBarChangeListener{

        public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
                //progress为当前数值的大小
                mProgressText.setText("当前值:" + progress);
        }

        @Override
        //在拖动中会调用此方法
        public void onStartTrackingTouch(SeekBar seekBar) {
                mTrackingText.setText("正在调节");
        }

        @Override
        //停止拖动
        public void onStopTrackingTouch(SeekBar seekBar) {
                mTrackingText.setText("停止调节");

        }

     }
}

运行结果：

Focus on technology, enjoy life！—— QQ：804212028
浏览链接：http://blog.csdn.net/y18334702058/article/details/44624305