Android 自定义Dialog 实例

开发中经常需要请求网络获取数据，我们在请求网络到得到数据时当中需要等待一些时间，为了增加用户体验，我们一般会用一个dialog来提示用户我们在加载网络数据。

今天我们来实现如下效果的加载中dialog。

 

从图中我们可以看到要这个dialog是图片还有文字组成的，(不过我这里使用代码实现的，没有用图片)，以下是这个加载图形的代码：

public class lvcircularring extends view {

private float mwidth = 0f;
private float mpadding = 0f;
private float startangle = 0f;
private paint mpaint;

public lvcircularring(context context) {
 this(context, null);
}

public lvcircularring(context context, attributeset attrs) {
 this(context, attrs, 0);
}

public lvcircularring(context context, attributeset attrs, int defstyleattr) {
 super(context, attrs, defstyleattr);
 initpaint();
}

@override
protected void onmeasure(int widthmeasurespec, int heightmeasurespec) {
 super.onmeasure(widthmeasurespec, heightmeasurespec);

 if (getmeasuredwidth() > getheight())
  mwidth = getmeasuredheight();
 else
  mwidth = getmeasuredwidth();
 mpadding = 5;
}

@override
protected void ondraw(canvas canvas) {
 super.ondraw(canvas);

 mpaint.setcolor(color.argb(100, 255, 255, 255));
 canvas.drawcircle(mwidth / 2, mwidth / 2, mwidth / 2 - mpadding, mpaint);
 mpaint.setcolor(color.white);
 rectf rectf = new rectf(mpadding, mpadding, mwidth - mpadding, mwidth - mpadding);
 canvas.drawarc(rectf, startangle, 100
   , false, mpaint);//第四个参数是否显示半径

}


private void initpaint() {
 mpaint = new paint();
 mpaint.setantialias(true);
 mpaint.setstyle(paint.style.stroke);
 mpaint.setcolor(color.white);
 mpaint.setstrokewidth(8);
}

public void startanim() {
 stopanim();
 startviewanim(0f, 1f, 1000);
}

public void stopanim() {
 if (valueanimator != null) {
  clearanimation();
  valueanimator.setrepeatcount(1);
  valueanimator.cancel();
  valueanimator.end();
 }
}

valueanimator valueanimator;

private valueanimator startviewanim(float startf, final float endf, long time) {
 valueanimator = valueanimator.offloat(startf, endf);

 valueanimator.setduration(time);
 valueanimator.setinterpolator(new linearinterpolator());
 valueanimator.setrepeatcount(valueanimator.infinite);//无限循环
 valueanimator.setrepeatmode(valueanimator.restart);//

 valueanimator.addupdatelistener(new valueanimator.animatorupdatelistener() {
  @override
  public void onanimationupdate(valueanimator valueanimator) {

   float value = (float) valueanimator.getanimatedvalue();
   startangle = 360 * value;

   invalidate();
  }
 });
 valueanimator.addlistener(new animatorlisteneradapter() {
  @override
  public void onanimationend(animator animation) {
   super.onanimationend(animation);
  }
 });
 if (!valueanimator.isrunning()) {
  valueanimator.start();
 }

 return valueanimator;
}
}

 dialog 代码：

public class loadingdialog {
lvcircularring mloadingview;
dialog mloadingdialog;

public loadingdialog(context context,string msg) {
 // 首先得到整个view
 view view = layoutinflater.from(context).inflate(
   r.layout.loading_dialog_view, null);
 // 获取整个布局
 linearlayout layout = (linearlayout) view.findviewbyid(r.id.dialog_view);
 // 页面中的loadingview
 mloadingview = (lvcircularring) view.findviewbyid(r.id.lv_circularring);
 // 页面中显示文本
 textview loadingtext = (textview) view.findviewbyid(r.id.loading_text);
 // 显示文本
 loadingtext.settext(msg);
 // 创建自定义样式的dialog
 mloadingdialog = new dialog(context, r.style.loading_dialog);
 // 设置返回键无效
 mloadingdialog.setcancelable(false);
 mloadingdialog.setcontentview(layout, new linearlayout.layoutparams(
   linearlayout.layoutparams.match_parent,
   linearlayout.layoutparams.match_parent));
}

public void show(){
 mloadingdialog.show();
 mloadingview.startanim();
}

public void close(){
 if (mloadingdialog!=null) {
  mloadingview.stopanim();
  mloadingdialog.dismiss();
  mloadingdialog=null;
 }
}
}

 布局文件loading_dialog_view 代码：

<?xml version="1.0" encoding="utf-8"?>
<linearlayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/dialog_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center"
android:background="@drawable/dialog_bg"
android:padding="20dp"
android:orientation="vertical">

<com.ye.daqiapp.ui.widget.loading.lvcircularring
 android:id="@+id/lv_circularring"
 android:layout_width="50dp"
 android:layout_height="50dp"/>

<textview
 android:id="@+id/loading_text"
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:textcolor="#ffffff"
 android:layout_margintop="5dp"
 android:textsize="15sp"/>

</linearlayout>

 dialog中style代码：

<style name="loading_dialog" parent="android:style/theme.dialog">
 <item name="android:windowframe">@null</item>
 <item name="android:windownotitle">true</item>
 <item name="android:windowbackground">@android:color/transparent</item>
 <item name="android:windowisfloating">true</item>
 <item name="android:backgrounddimenabled">false</item>
 <item name="android:windowcontentoverlay">@null</item>
</style>

 背景dialog_bg 代码：

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
<!-- 内部颜色 -->
<solid android:color="#444444" />

<!-- 圆角的幅度 -->
<corners
 android:bottomleftradius="3dp"
 android:bottomrightradius="3dp"
 android:topleftradius="3dp"
 android:toprightradius="3dp" />
</shape>

 如何使用：在需要使用的地方初始化dialog:

loadingdialog dialog=new loadingdialog(context,"玩命加载中...");
//显示dialog
dialog.show();
//关闭dialog
dialog.close();

以上是对android dialog 重写的小示例，有需要的朋友可以参考下。