Android自定义等待对话框

最近，看了好多的APP的等待对话框，发现自己的太lower，于是就研究了一番，最后经过苦心努力，实现一个。

• 自定义一个LoadingIndicatorView(extends View )类
• 编写values/attrs.xml，在其中编写styleable和item等标签元素
• 在布局文件中LoadingIndicatorView使用自定义的属性（注意namespace）
• 在LoadingIndicatorView的构造方法中通过TypedArray获取
  

描述就提供这些，一下是代码的展示，非常的详细。
1、自定义属性的声明文件

 
     
       
     
     
   




LoadingIndicatorView.java  



import android.annotation.TargetApi; 
import android.content.Context; 
import android.content.res.TypedArray; 
import android.graphics.Canvas; 
import android.graphics.Color; 
import android.graphics.Paint; 
import android.os.Build; 
import android.support.annotation.IntDef; 
import android.util.AttributeSet; 
import android.view.View; 
 
import com.chni.lidong.androidtestdemo.R; 
 
 
 
public class LoadingIndicatorView extends View { 
 
 
  //indicators 指示器 
  public static final int BallSpinFadeLoader=22; 
 
  @IntDef(flag = true, 
      value = { 
   BallSpinFadeLoader, 
      }) 
  public @interface Indicator{} 
 
  //Sizes (with defaults in DP) 
  public static final int DEFAULT_SIZE=45; 
 
  //attrs 
  int mIndicatorId; 
  int mIndicatorColor; 
 
  Paint mPaint; 
 
  baseIndicatorController mIndicatorController; 
 
  private boolean mHasAnimation; 
 
 
  public LoadingIndicatorView(Context context) { 
    super(context); 
    init(null, 0); 
  } 
 
  public LoadingIndicatorView(Context context, AttributeSet attrs) { 
    super(context, attrs); 
    init(attrs, 0); 
  } 
 
  public LoadingIndicatorView(Context context, AttributeSet attrs, int defStyleAttr) { 
    super(context, attrs, defStyleAttr); 
    init(attrs, defStyleAttr); 
  } 
 
 
  @TargetApi(Build.VERSION_CODES.LOLLIPOP) 
  public LoadingIndicatorView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) { 
    super(context, attrs, defStyleAttr, defStyleRes); 
    init(attrs, defStyleAttr); 
  } 
 
  private void init(AttributeSet attrs, int defStyle) { 
     
    TypedArray a = getContext().obtainStyledAttributes(attrs, R.styleable.AVLoadingIndicatorView); 
    mIndicatorId=a.getInt(R.styleable.AVLoadingIndicatorView_indicator, BallSpinFadeLoader);//获取编号属性 
    mIndicatorColor=a.getColor(R.styleable.AVLoadingIndicatorView_indicator_color, Color.WHITE);//获取颜色属性 
    a.recycle();//回收属性的集合 
    mPaint=new Paint(); 
    mPaint.setColor(mIndicatorColor);//设置画笔的颜色 
    mPaint.setStyle(Paint.Style.FILL);//设置画笔的样式为填充 
    mPaint.setAntiAlias(true);//去锯齿 
    applyIndicator();// 
  } 
 
  private void applyIndicator(){ 
    switch (mIndicatorId){ 
      case BallSpinFadeLoader: 
 mIndicatorController=new BallSpinFadeLoaderIndicator(); 
 break; 
    } 
    mIndicatorController.setTarget(this);//将控件设置到当前View 
  } 
 
  @Override 
  protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { 
    int width = measureDimension(dp2px(DEFAULT_SIZE), widthMeasureSpec);//获取View的宽度 
    int height = measureDimension(dp2px(DEFAULT_SIZE), heightMeasureSpec);//获取View的高度 
    setMeasuredDimension(width, height);// 
  } 
 
   
  private int measureDimension(int defaultSize,int measureSpec){ 
    int result = defaultSize; 
    int specMode = MeasureSpec.getMode(measureSpec);//测量规范 
    int specSize = MeasureSpec.getSize(measureSpec);//测量大小 
    if (specMode == MeasureSpec.EXACTLY) {//父控件已经为子控件设置确定的大小，子控件会考虑父控件给他的大小，自己需要多大设置多大 
      result = specSize; 
    } else if (specMode == MeasureSpec.AT_MOST) {//子控件可以设置自己希望的指定大小 
      result = Math.min(defaultSize, specSize);//取最小值 
    } else { 
      result = defaultSize; 
    } 
    return result; 
  } 
 
  @Override 
  protected void onDraw(Canvas canvas) { 
    super.onDraw(canvas); 
    drawIndicator(canvas); 
  } 
 
  @Override 
  protected void onLayout(boolean changed, int left, int top, int right, int bottom) { 
    super.onLayout(changed, left, top, right, bottom); 
    if (!mHasAnimation){ 
      mHasAnimation=true; 
      applyAnimation(); 
    } 
  } 
 
  void drawIndicator(Canvas canvas){ 
    mIndicatorController.draw(canvas,mPaint); 
  } 
 
  void applyAnimation(){ 
    mIndicatorController.createAnimation(); 
  } 
 
  private int dp2px(int dpValue) { 
    return (int) getContext().getResources().getDisplayMetrics().density * dpValue; 
  } 


baseIndicatorController.java 



package com.chni.lidong.androidtestdemo.loading; 
 
import android.graphics.Canvas; 
import android.graphics.Paint; 
import android.view.View; 
 
 
public abstract class baseIndicatorController { 
 
  private View mTarget; 
 
 
  public void setTarget(View target){ 
    this.mTarget=target; 
  } 
 
  public View getTarget(){ 
    return mTarget; 
  } 
 
   
  public int getWidth(){ 
    return mTarget.getWidth(); 
  } 
 
   
  public int getHeight(){ 
    return mTarget.getHeight(); 
  } 
 
   
  public void postInvalidate(){ 
    mTarget.postInvalidate(); 
  } 
 
   
  public abstract void draw(Canvas canvas,Paint paint); 
 
   
  public abstract void createAnimation(); 
 
 
} 


 BallSpinFadeLoaderIndicator.java



package com.chni.lidong.androidtestdemo.loading; 
 
import android.graphics.Canvas; 
import android.graphics.Paint; 
 
import com.nineoldandroids.animation.ValueAnimator; 
 
 
public class BallSpinFadeLoaderIndicator extends baseIndicatorController { 
 
  public static final float SCALE=1.0f; 
 
  public static final int ALPHA=255; 
   
  float[] scaleFloats=new float[]{SCALE, 
      SCALE, 
      SCALE, 
      SCALE, 
      SCALE, 
      SCALE, 
      SCALE, 
      SCALE}; 
   
  int[] alphas=new int[]{ALPHA, 
      ALPHA, 
      ALPHA, 
      ALPHA, 
      ALPHA, 
      ALPHA, 
      ALPHA, 
      ALPHA}; 
 
 
  @Override 
  public void draw(Canvas canvas, Paint paint) { 
    float radius=getWidth()/10; 
    for (int i = 0; i < 8; i++) { 
      canvas.save(); 
      Point point=circleAt(getWidth(),getHeight(),getWidth()/2-radius,i*(Math.PI/4)); 
      canvas.translate(point.x,point.y); 
      canvas.scale(scaleFloats[i],scaleFloats[i]); 
      paint.setAlpha(alphas[i]); 
      canvas.drawCircle(0,0,radius,paint); 
      canvas.restore(); 
    } 
  } 
 
   
  Point circleAt(int width,int height,float radius,double angle){ 
    float x= (float) (width/2+radius*(Math.cos(angle))); 
    float y= (float) (height/2+radius*(Math.sin(angle))); 
    return new Point(x,y); 
  } 
 
  @Override 
  public void createAnimation() { 
    int[] delays= {0, 120, 240, 360, 480, 600, 720, 780, 840}; 
    for (int i = 0; i < 8; i++) { 
      final int index=i; 
      ValueAnimator scaleAnim=ValueAnimator.ofFloat(1,0.4f,1);//创建ValueAnimator对象 
      scaleAnim.setDuration(1000);//设置动画的持续时间 
      scaleAnim.setRepeatCount(-1);//设置动画是否重复 
      scaleAnim.setStartDelay(delays[i]);//延迟启动动画 
      scaleAnim.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {//ValueAnimator只负责第一次的内容，因此必须通过监听来实现对象的相关属性的更新 
 @Override 
 public void onAnimationUpdate(ValueAnimator animation) { 
   scaleFloats[index] = (float) animation.getAnimatedValue();//获取当前帧的值 
   postInvalidate(); 
 } 
      }); 
      scaleAnim.start();//启动属性动画 
 
      ValueAnimator alphaAnim=ValueAnimator.ofInt(255, 77, 255);//透明度动画 
      alphaAnim.setDuration(1000);// 
      alphaAnim.setRepeatCount(-1); 
      alphaAnim.setStartDelay(delays[i]); 
      alphaAnim.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() { 
 @Override 
 public void onAnimationUpdate(ValueAnimator animation) { 
   alphas[index] = (int) animation.getAnimatedValue(); 
   postInvalidate(); 
 } 
      }); 
      alphaAnim.start(); 
    } 
  } 
 
  final class Point{ 
    public float x; 
    public float y; 
 
    public Point(float x, float y){ 
      this.x=x; 
      this.y=y; 
    } 
  } 
 
 
} 


UIHelp.java



package com.chni.lidong.androidtestdemo.utils; 
 
import android.app.Activity; 
import android.app.Dialog; 
import android.view.LayoutInflater; 
import android.view.View; 
import android.widget.LinearLayout; 
import android.widget.TextView; 
 
import com.chni.lidong.androidtestdemo.R; 
 
 
public class UIHelper { 
   
   
  private static Dialog mLoadingDialog; 
   
   
   
  public static void showDialogForLoading(Activity context, String msg, boolean cancelable) { 
    View view = LayoutInflater.from(context).inflate(R.layout.layout_loading_dialog, null); 
    TextView loadingText = (TextView)view.findViewById(R.id.id_tv_loading_dialog_text); 
    loadingText.setText(msg); 
     
    mLoadingDialog = new Dialog(context, R.style.loading_dialog_style); 
    mLoadingDialog.setCancelable(cancelable); 
    mLoadingDialog.setContentView(view, new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.MATCH_PARENT)); 
    mLoadingDialog.show();    
  } 
   
   
  public static void hideDialogForLoading() { 
    if(mLoadingDialog != null && mLoadingDialog.isShowing()) { 
      mLoadingDialog.cancel(); 
    } 
  } 
 
} 


对话框的布局：





  

    

  

  





对话框的样式：





  @null
  true
  @color/transparent
  true
  @null



MainActivity.java



public class Main7Activity extends AppCompatActivity { 
 
  @Override 
  protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main7); 
    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar); 
    setSupportActionBar(toolbar); 
 
    FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab); 
    fab.setonClickListener(new View.onClickListener() { 
      @Override 
      public void onClick(View view) { 
 Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG) 
     .setAction("Action", null).show(); 
      } 
    }); 
    UIHelper.showDialogForLoading(this, "正在加载...", true); 
    Handler handler = new Handler(); 
    handler.postDelayed(new Runnable() { 
      @Override 
      public void run() { 
 UIHelper.hideDialogForLoading(); 
      } 
    },10000); 
  } 
 
} 

效果图;

以上就是本文的全部内容，希望对大家的学习有所帮助。