Android原生控件 -- AlertDialog（警示对话框）

⒈使用

　　普通使用

        AlertDialog.Builder builder = new AlertDialog.Builder(getApplicationContext());
        builder.setTitle("请回答:");
        builder.setMessage("你觉得蔡徐坤球技如何？");
        builder.setIcon(R.drawable.icon_user);
        builder.setPositiveButton("棒", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                Toast.makeText(getApplicationContext(),"我看你是个智障",Toast.LENGTH_LONG).show();
            }
        });
        builder.setNeutralButton("还行", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                Toast.makeText(getApplicationContext(),"我看你视力并不怎么好",Toast.LENGTH_LONG).show();
            }
        });
        builder.setNegativeButton("垃圾", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                Toast.makeText(getApplicationContext(),"你很诚实",Toast.LENGTH_LONG).show();
            }
        });
        builder.show();

　　单选框形式

        AlertDialog.Builder builder = new AlertDialog.Builder(getApplicationContext());
        builder.setTitle("选择性别:");
        final String[] array = new String[]{"男","女"};
        builder.setItems(array, new DialogInterface.OnClickListener() {
            /**
             *
             * @param dialog
             * @param which 选中的数组索引
             */
            @Override
            public void onClick(DialogInterface dialog, int which) {
                Toast.makeText(getApplicationContext(),"您选中了 " + array[which],Toast.LENGTH_LONG).show();
            }
        });

　　单选按钮形式

        AlertDialog.Builder builder = new AlertDialog.Builder(getApplicationContext());
        builder.setTitle("选择性别:");
        final String[] array = new String[]{"男","女"};
        builder.setSingleChoiceItems(array, 0, new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                Toast.makeText(getApplicationContext(),"您选中了 " + array[which],Toast.LENGTH_LONG).show();
            }
        });

　　默认情况下点击弹出框其他区域 弹出框将会消失，通过以下方式禁用。

builder.setCancelable(false);

　　默认情况下点击弹出框的选项弹出框并不会消息，通过以下方式使其消失。

            @Override
            public void onClick(DialogInterface dialog, int which) {
                Toast.makeText(getApplicationContext(),"您选中了 " + array[which],Toast.LENGTH_LONG).show();
                dialog.dismiss();
            }

　　多选

        AlertDialog.Builder builder = new AlertDialog.Builder(getApplicationContext());
        builder.setTitle("选择你的特长:");
        final String[] array = new String[]{"唱歌","跳舞","编程","泡妞"};
        boolean[] isSelected = new boolean[]{false,false,true,true};
        builder.setMultiChoiceItems(array, isSelected, new DialogInterface.OnMultiChoiceClickListener() {
            /**
             *
             * @param dialog
             * @param which 表示点击的索引
             * @param isChecked 标识当前点击的选中状态
             */
            @Override
            public void onClick(DialogInterface dialog, int which, boolean isChecked) {
                Toast.makeText(getApplicationContext(),array[which] + ":" + isChecked,Toast.LENGTH_LONG).show();
                dialog.dismiss();
            }
        });

 　　自定义布局视图展示

        AlertDialog.Builder builder = new AlertDialog.Builder(getApplicationContext());
        builder.setTitle("请先登录");
        View view = LayoutInflater.from(getApplicationContext()).inflate(R.layout.layout_dialog,null);
        EditText etUserName = view.findViewById(R.id.et_username);
        EditText etPassWord = view.findViewById(R.id.et_password);
        Button btnLogin = view.findViewById(R.id.btn_login);
        builder.setView(view).show();