本文實例講述了Android編程實現(xiàn)可滑動的開關(guān)效果。分享給大家供大家參考,具體如下:
閑著沒事,把之前寫的一個Demo放上來分享下。就是一個開關(guān),實現(xiàn)可滑動和動畫效果。不是圖片切換。
好了,先上圖:

完整實例代碼點擊此處本站下載。
直接把自定義的這個View代碼放上來,有注釋應該很好理解:
首先是布局:
<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/sv_container" android:layout_width="230dip" android:layout_height="38dip" android:background="@drawable/usage_list_dark" > <ImageView android:id="@+id/iv_switch_cursor" android:layout_width="120dip" android:layout_height="36dip" android:layout_centerVertical="true" android:layout_marginLeft="0.5dip" android:layout_marginRight="0.5dip" android:background="@drawable/usage_list_green" /> <LinearLayout android:layout_width="fill_parent" android:layout_height="fill_parent" android:gravity="center" > <TextView android:id="@+id/switch_text_true" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_weight="1" android:gravity="center" android:text="開" /> <TextView android:id="@+id/switch_text_false" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_weight="1" android:gravity="center" android:text="關(guān)" /> </LinearLayout></RelativeLayout>
接著是這個View的代碼,繼承自LinearLayout :
package com.lxb.switchdemo;import android.content.Context;import android.graphics.Color;import android.os.Handler;import android.os.Message;import android.view.LayoutInflater;import android.view.MotionEvent;import android.view.View;import android.view.View.OnClickListener;import android.view.animation.Animation;import android.view.animation.Animation.AnimationListener;import android.view.animation.LinearInterpolator;import android.view.animation.TranslateAnimation;import android.widget.ImageView;import android.widget.LinearLayout;import android.widget.RelativeLayout;import android.widget.TextView;public class SwitchView extends LinearLayout implements OnClickListener {  private static final int FLAG_MOVE_TRUE = 1; // 向左滑動標識  private static final int FLAG_MOVE_FALSE = 2; // 向右滑動標識  private static final int HANDLE_LAYOUT_CURSOR = 100; // 處理調(diào)用開關(guān)的layout方法  private Context context; // 上下文對象  private RelativeLayout sv_container; // SwitchView的外層Layout  private ImageView iv_switch_cursor; // 開關(guān)郵標的ImageView  private TextView switch_text_true; // true的文字信息控件  private TextView switch_text_false; // false的文字信息控件  private boolean isChecked = true; // 是否已開  private boolean checkedChange = false; // isChecked是否有改變  private OnCheckedChangeListener onCheckedChangeListener; // 用于監(jiān)聽isChecked是否有改變  private int margin = 1; // 游標離邊緣位置(這個值視圖片而定, 主要是為了圖片能顯示正確)  private int bg_left; // 背景左  private int bg_right; // 背景右  private int cursor_left; // 游標左部  private int cursor_top; // 游標頂部  private int cursor_right; // 游標右部  private int cursor_bottom; // 游標底部  private Animation animation; // 移動動畫  private int currentFlag = FLAG_MOVE_TRUE; // 當前移動方向flag  public SwitchView(Context context) {    super(context);    this.context = context;    initView();  }  @Override  protected void onLayout(boolean changed, int l, int t, int r, int b) {    super.onLayout(changed, l, t, r, b);    // 獲取所需要的值    bg_left = sv_container.getLeft();    bg_right = sv_container.getRight();    cursor_left = iv_switch_cursor.getLeft();    cursor_top = iv_switch_cursor.getTop();    cursor_right = iv_switch_cursor.getRight();    cursor_bottom = iv_switch_cursor.getBottom();  }  private Handler mHandler = new Handler() {    @Override    public void handleMessage(Message msg) {      switch(msg.what) {      case HANDLE_LAYOUT_CURSOR:        iv_switch_cursor.layout(cursor_left, cursor_top, cursor_right, cursor_bottom);        break;      }    }  };  public void onClick(View v) {    // 控件點擊時觸發(fā)改變checked值    if(v == this) {      changeChecked(!isChecked);    }  }  /**   * 初始化控件   */  private void initView() {    LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);    View view = inflater.inflate(R.layout.switch_view, this);    view.setOnClickListener(this);    sv_container = (RelativeLayout) view.findViewById(R.id.sv_container);    switch_text_true = (TextView) view.findViewById(R.id.switch_text_true);    switch_text_false = (TextView) view.findViewById(R.id.switch_text_false);    changeTextColor();    iv_switch_cursor = (ImageView) view.findViewById(R.id.iv_switch_cursor);    iv_switch_cursor.setClickable(false);    iv_switch_cursor.setOnTouchListener(new OnTouchListener() {      int lastX; // 最后的X坐標      public boolean onTouch(View v, MotionEvent event) {        switch(event.getAction()) {        case MotionEvent.ACTION_DOWN:          lastX = (int) event.getRawX();          cursor_left = v.getLeft();          cursor_top = v.getTop();          cursor_right = v.getRight();          cursor_bottom = v.getBottom();          break;        case MotionEvent.ACTION_MOVE:          int dx = (int) event.getRawX() - lastX;          cursor_left = v.getLeft() + dx;          cursor_right = v.getRight() + dx;          // 超出邊界處理          if(cursor_left <= bg_left + margin) {            cursor_left = bg_left + margin;            cursor_right = cursor_left + v.getWidth();          }          if(cursor_right >= bg_right - margin) {            cursor_right = bg_right - margin;            cursor_left = cursor_right - v.getWidth();          }          v.layout(cursor_left, cursor_top, cursor_right, cursor_bottom);          lastX = (int) event.getRawX();          break;        case MotionEvent.ACTION_UP:          calculateIscheck();          break;        }        return true;      }    });  }  /**   * 計算處于true或是false區(qū)域, 并做改變處理   */  private void calculateIscheck() {    float center = (float) ((bg_right - bg_left) / 2.0);    float cursor_center = (float) ((cursor_right - cursor_left) / 2.0);    if(cursor_left + cursor_center <= center) {      changeChecked(true);    } else {      changeChecked(false);    }  }  /**   * 改變checked, 根據(jù)checked移動游標   * @param isChecked   */  private void changeChecked(boolean isChecked) {    if(this.isChecked != isChecked) {      checkedChange = true;    } else {      checkedChange = false;    }    if(isChecked) {      currentFlag = FLAG_MOVE_TRUE;    } else {      currentFlag = FLAG_MOVE_FALSE;    }    cursorMove();  }  /**   * 游標移動   */  private void cursorMove() {    // 這里說明一點, 動畫本可設置animation.setFillAfter(true)    // 令動畫進行完后停在最后位置. 但這里使用這樣方式的話.    // 再次拖動圖片會出現(xiàn)異常(具體原因我沒找到)    // 所以最后只能使用onAnimationEnd回調(diào)方式再layout游標    animation = null;    final int toX;    if(currentFlag == FLAG_MOVE_TRUE) {      toX = cursor_left - bg_left - margin;      animation = new TranslateAnimation(0, -toX, 0, 0);    } else {      toX = bg_right - margin - cursor_right;      animation = new TranslateAnimation(0, toX, 0, 0);    }    animation.setDuration(100);    animation.setInterpolator(new LinearInterpolator());    animation.setAnimationListener(new AnimationListener() {      public void onAnimationStart(Animation animation) {      }      public void onAnimationRepeat(Animation animation) {      }      public void onAnimationEnd(Animation animation) {        // 計算動畫完成后游標應在的位置        if(currentFlag == FLAG_MOVE_TRUE) {          cursor_left -= toX;          cursor_right = cursor_left + iv_switch_cursor.getWidth();        } else {          cursor_right = bg_right - margin;          cursor_left = cursor_right - iv_switch_cursor.getWidth();        }        // 這里不能馬上layout游標正確位置, 否則會有一點點閃屏        // 為了美觀, 這里遲了一點點調(diào)用layout方法, 便不會閃屏        mHandler.sendEmptyMessageDelayed(HANDLE_LAYOUT_CURSOR, 5);        // 這里是根據(jù)是不是改變了isChecked值進行一些操作        if(checkedChange) {          isChecked = !isChecked;          if(onCheckedChangeListener != null) {            onCheckedChangeListener.onCheckedChanged(isChecked);          }          changeTextColor();        }      }    });    iv_switch_cursor.startAnimation(animation);  }  /**   * 改變字體顯示顏色   */  private void changeTextColor() {    if(isChecked) {      switch_text_true.setTextColor(Color.WHITE);      switch_text_false.setTextColor(Color.GRAY);    } else {      switch_text_true.setTextColor(Color.GRAY);      switch_text_false.setTextColor(Color.WHITE);    }  }  /**   * layout游標   */  private void layoutCursor() {    if(isChecked) {      cursor_left = bg_left + margin;      cursor_right = bg_left + margin + iv_switch_cursor.getWidth();    } else {      cursor_left = bg_right - margin - iv_switch_cursor.getWidth();      cursor_right = bg_right - margin;    }    iv_switch_cursor.layout(cursor_left, cursor_top, cursor_right, cursor_bottom);  }  /**   * isChecked值改變監(jiān)聽器   */  public interface OnCheckedChangeListener {    void onCheckedChanged(boolean isChecked);  }  public boolean isChecked() {    return isChecked;  }  public void setChecked(boolean isChecked) {    if(this.isChecked != isChecked) {      this.isChecked = isChecked;      if(onCheckedChangeListener != null) {        onCheckedChangeListener.onCheckedChanged(isChecked);      }      layoutCursor();    }  }  public void setOnCheckedChangeListener(      OnCheckedChangeListener onCheckedChangeListener) {    this.onCheckedChangeListener = onCheckedChangeListener;  }}最后是Activity使用這個View:
package com.lxb.switchdemo;import android.app.Activity;import android.os.Bundle;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;import android.widget.LinearLayout;import android.widget.TextView;import android.widget.Toast;import com.lxb.switchdemo.SwitchView.OnCheckedChangeListener;public class Switch_demoActivity extends Activity implements OnClickListener {  private LinearLayout layout;  private TextView tv_showcheck;  private SwitchView sv;  private Button btn_set_true;  private Button btn_set_false;  private Button btn_getstate;  @Override  public void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.main);    layout = (LinearLayout) findViewById(R.id.layout);    tv_showcheck = (TextView) findViewById(R.id.tv_showcheck);    sv = new SwitchView(this);    tv_showcheck.setText("當前狀態(tài): " + getState(sv.isChecked()));    sv.setOnCheckedChangeListener(new OnCheckedChangeListener() {      public void onCheckedChanged(boolean isChecked) {        tv_showcheck.setText("當前狀態(tài): " + getState(isChecked));      }    });    layout.addView(sv);    btn_set_true = (Button) findViewById(R.id.btn_set_true);    btn_set_false = (Button) findViewById(R.id.btn_set_false);    btn_getstate = (Button) findViewById(R.id.btn_getstate);    btn_set_true.setOnClickListener(this);    btn_set_false.setOnClickListener(this);    btn_getstate.setOnClickListener(this);  }  public void onClick(View v) {    switch(v.getId()) {    case R.id.btn_set_true:      sv.setChecked(true);      break;    case R.id.btn_set_false:      sv.setChecked(false);      break;    case R.id.btn_getstate:      Toast.makeText(Switch_demoActivity.this,          sv.isChecked() + "", Toast.LENGTH_SHORT).show();      break;    }  }  private String getState(boolean state) {    if(state) {      return "開";    }    return "關(guān)";  }}實現(xiàn)起來還是很簡單的,主要還是坐標什么的需要計算與調(diào)整。
當然可能還會有一些BUG存在,有需要的可以下下來自行修改,也可以和我討論。
更多關(guān)于Android相關(guān)內(nèi)容感興趣的讀者可查看本站專題:《Android通信方式總結(jié)》、《Android調(diào)試技巧與常見問題解決方法匯總》、《Android開發(fā)入門與進階教程》、《Android多媒體操作技巧匯總(音頻,視頻,錄音等)》、《Android基本組件用法總結(jié)》、《Android視圖View技巧總結(jié)》、《Android布局layout技巧總結(jié)》及《Android控件用法總結(jié)》
希望本文所述對大家Android程序設計有所幫助。
新聞熱點
疑難解答