(3)Dialog && picker

public void showDiag1(View v){
        AlertDialog.Builder builder = new AlertDialog.Builder(this);
        builder.setTitle("登录");
        builder.setMessage("请确认你是否要登录？");
        builder.setPositiveButton("确定", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                Toast.makeText(MainActivity.this,"you choose 确定",Toast.LENGTH_SHORT).show();
            }
        });

        builder.setNegativeButton("取消", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                Toast.makeText(MainActivity.this,"you choose 取消",Toast.LENGTH_SHORT).show();
            }
        });
        builder.show();
    }

 public void showDiag2(View v){
        AlertDialog.Builder builder = new AlertDialog.Builder(this);
        builder.setTitle("登录");
        final String[] strings = {"1","2","3","4"};
        final boolean[] chooses = {false,false,false,false};
        builder.setMultiChoiceItems(strings, chooses, new DialogInterface.OnMultiChoiceClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which, boolean isChecked) {

            }
        });

        builder.setPositiveButton("确定", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                String context = "";
                for(int i=0;i<chooses.length;i++){
                    if(chooses[i]) {
                        context += strings[i];
                    }
                }
                Toast.makeText(MainActivity.this,"you choose:"+context,Toast.LENGTH_SHORT).show();

            }
        });

        builder.setNegativeButton("取消", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                Toast.makeText(MainActivity.this,"you choose 取消",Toast.LENGTH_SHORT).show();
            }
        });
        builder.show();

    }
}