常见对话框

(1)普通对话框

// 点击按钮 弹出一个普通对话框
    public void click1(View v) {

        // 构建AlertDialog
        AlertDialog.Builder builder = new Builder(this);
        builder.setTitle("警告");
        builder.setMessage("世界上最遥远的距离是没有网络");
        builder.setPositiveButton("确定", new OnClickListener() {

            @Override
            public void onClick(DialogInterface dialog, int which) {

                System.out.println("点击了确定按钮 执行的逻辑");

            }
        });
        builder.setNegativeButton("取消", new OnClickListener() {

            @Override
            public void onClick(DialogInterface dialog, int which) {

                System.out.println("点击了取消按钮");
            }
        });
        // 最后一步一定要记得 show出来
        builder.show();

    }

(2)单选对话框

// 点击按钮 弹出一个单选对话框
    public void click2(View v) {

        // 构建AlertDialog
        AlertDialog.Builder builder = new Builder(this);
        builder.setTitle("请选择您喜欢的课");
        final String items[] = { "Android", "ios", "php", "c", "C++", "html" };
        builder.setSingleChoiceItems(items, -1, new OnClickListener() {

            @Override
            public void onClick(DialogInterface dialog, int which) {

                // 取出点中的条目
                String item = items[which];
                Toast.makeText(getApplicationContext(), item, 1).show();
                // 关闭当前对话框
                dialog.dismiss();
            }
        });

        // 最后一步一定要记得 show出来
        builder.show();

    }

(3)多选对话框

// 点击按钮 弹出一个多选对话框
    public void click3(View v) {
        // 构建AlertDialog
        AlertDialog.Builder builder = new Builder(this);
        builder.setTitle("请选择您喜欢吃的水果");
        final String items[] = { "榴莲", "苹果", "葡萄", "香蕉", "黄瓜", "火龙果", "荔枝" };
        final boolean[] checkedItems = { true, false, false, false, false,
                false, true };
        builder.setMultiChoiceItems(items, checkedItems,
                new OnMultiChoiceClickListener() {

                    @Override
                    public void onClick(DialogInterface dialog, int which,
                            boolean isChecked) {

                    }
                });
        builder.setPositiveButton("确定", new OnClickListener() {

            @Override
            public void onClick(DialogInterface dialog, int which) {

                StringBuffer sb = new StringBuffer();
                // [1]把你选中的水果给取出来
                for (int i = 0; i < checkedItems.length; i++) {
                    if (checkedItems[i]) {
                        // 就证明是选中的
                        String fruit = items[i];
                        sb.append(fruit + " ");

                    }

                }

                Toast.makeText(getApplicationContext(), sb.toString(), 1)
                        .show();
                // 关闭对话框
                dialog.dismiss();

            }
        });

        // 最后一步一定要记得 show出来
        builder.show();

    }

(4)进度条对话框

//进度条对话框
    public void click4(View v) {

        //与进度相关的控件都可以直接在子线程更新ui 
        final ProgressDialog dialog = new ProgressDialog(this);
        dialog.setTitle("正在玩命加载ing");
        dialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
        dialog.show();
        //设置进度条的最大值 
        dialog.setMax(100);
        new Thread(){public void run() {
            for (int i = 0; i <= 100; i++) {
                //设置当前的进度 
                
                SystemClock.sleep(50);//睡眠50毫秒
                dialog.setProgress(i);
            }
            //关闭对话框
            dialog.dismiss();
            
            
        };}.start();
        
        
    }

 

补充 2种上下文的区别

this:mainActivity 子类 

getApplicationContext(): 返回Context 父类

对话框不能用getApplicationContext();