Android 拖動條(SeekBar)實例 附完整demo項目代碼
1、拖動條的事件
實現SeekBar.OnSeekBarChangeListener接口。需要監聽三個事件:
數值改變(onProgressChanged)
開始拖動(onStartTrackingTouch)
停止拖動(onStopTrackingTouch)
onStartTrackingTouch開始拖動時觸發,與onProgressChanged區別是停止拖動前只觸發一次
而onProgressChanged只要在拖動,就會重復觸發。
2、拖動條的主要屬性和方法
setMax
設置拖動條的數值
setProgress
設置拖動條當前的數值
setSeconddaryProgress
設置第二拖動條的數值,即當前拖動條推薦的數值
代碼:
1 package com.zdztools.seekbartest; 2 3 import android.app.Activity; 4 import android.os.Bundle; 5 import android.util.Log; 6 import android.widget.SeekBar; 7 import android.widget.TextView; 8 import android.widget.SeekBar.OnSeekBarChangeListener; 9 10 public class MainActivity extends Activity { 11 protected static final String TAG = "MainActivity"; 12 private SeekBar seek; 13 private TextView myTextView; 14 15 @Override 16 protected void onCreate(Bundle savedInstanceState) { 17 super.onCreate(savedInstanceState); 18 setContentView(R.layout.activity_main); 19 20 myTextView = (TextView) findViewById(R.id.myTextView); 21 seek = (SeekBar) findViewById(R.id.mySeekBar); 22 //初始化 23 seek.setProgress(60); 24 seek.setOnSeekBarChangeListener(seekListener); 25 myTextView.setText("當前值 為: -" + 60); 26 } 27 28 private OnSeekBarChangeListener seekListener = new OnSeekBarChangeListener(){ 29 @Override 30 public void onStopTrackingTouch(SeekBar seekBar) { 31 Log.i(TAG,"onStopTrackingTouch"); 32 } 33 34 @Override 35 public void onStartTrackingTouch(SeekBar seekBar) { 36 Log.i(TAG,"onStartTrackingTouch"); 37 } 38 39 @Override 40 public void onProgressChanged(SeekBar seekBar, int progress, 41 boolean fromUser) { 42 Log.i(TAG,"onProgressChanged"); 43 myTextView.setText("當前值 為: -" + progress); 44 45 } 46 }; 47 }
<LinearLayout 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" 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" > <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_margin="20dip" android:text="" android:textSize="16sp" android:textStyle="bold" /> <SeekBar android:id="@+id/mySeekBar" android:layout_width="fill_parent" android:layout_height="wrap_content" /> </LinearLayout>
運行效果圖:
完整項目實例代碼:SeekBarTest.zip
本人另外一篇博客:android三檔自定義滑動開關,禁止點擊功能的實現,用默認的seekbar組件實現