常用控件的使用方法

1.TextView:
 
 
 

  match_parent：当前控件大小和父布局一样
 
 
 

  wrap_parent:控件大小刚好包住内容
 
 
 

  anroid:gravity="center" :居中
 
 
 

   
 
 
 

  2.EditText:
 
 
 

  anroid:hint="Type something here" //提示性文本
 
 
 

  anroid:maxLines="2" //最大行数，文本向上滚动
 
 
 

   
 
 
 

  3.ImageView:
 
 
 

  anroid:src //picture's location
 
 
 

  imageView.setImageResource(R.drawable.flower) //点击按钮切换图片
 
 
 

  in android studio the image's format must .png
 
 
 

   
 
 
 

  4.ProgressBar:
 
 
 

   设置控件是否可见:
  
 
  

   if(progressBar.getVisibility() == View.GONE){
  
 
  

                      progressBar.setVisibility(View.VISIBLE);
  
 
  

       }else{
  
 
  

                       progressBar.setVisibility(View.GONE);
  
 
  

                   }
  
 
 

  加减进度条:
 
 
 

                   int progress = progressBar.getProgress();
  
 
  

                   progress += 10;
  
 
  

                   progressBar.setProgress(progress);
  
 
 

   
 
 
 

  样式： style="?android:attr/progressBarStyleHorizontal"
 
 
 

   
 
 
 

  5.AlertDialog：//弹出提示框
 
 
 

  AlertDialog.Builder dialog =  new AlertDialog.Builder(MainActivity.this);
 
 
 

  dialog.setTitle
 
 
 

  dialog.setMessage
 
 
 

  dialog.setCancelable  //是否能通过BACK退出对话 FALSE为不允许
 
 
 

  //对话中按键监听事件
 
 
 

  dialog.setPositiveButton("OK",new DialogInterface.OnClickListener() {
 
 
 

                      @Override
 
 
 

                      public void onClick(DialogInterface dialog, int which) {
 
 
 

                          imageView.setImageResource(R.drawable.a1);
 
 
 

                      }
 
 
 

                  });
 
 
 

                  dialog.setNegativeButton("Cancel",new DialogInterface.OnClickListener() {
 
 
 

                      @Override
 
 
 

                      public void onClick(DialogInterface dialog, int which) {
 
 
 

   
 
 
 

                      }
 
 
 

                  });
 
 
 

   
 
 
 

  6.Loading框
 
 
 

  ProgressDialog.Builder dialog =  new ProgressDialog.Builder(MainActivity.this);
 
 
 

                  dialog.setTitle("this is Dialog");
 
 
 

                  dialog.setMessage("Loading...");
 
 
 

                  dialog.setCancelable(false); //在代码中设置好控制取消，调用dismiss()
 
 
 

   dialog.show();