Android Dialog使用详解

对话框是提示用户作出决定或输入额外信息的小窗口，通常不会填充整个屏幕，用于进行一些额外交互

Dialog 类是对话框的基类，但应该避免直接实例化 Dialog，而应使用其子类，比如

AlertDialog
此对话框可显示标题、提示信息、按钮、可选择项列表或自定义布局等
DatePickerDialog 或 TimePickerDialog
此类对话框带有允许用户选择日期或时间的预定义 UI

这些类定义了对话框的样式和结构，但开发者应该将 DialogFragment 用作对话框的容器。DialogFragment 类提供了创建对话框和管理其外观所需的所有控件，而不是调用 Dialog 对象上的方法
使用 DialogFragment 管理对话框可确保它能正确处理生命周期事件，如用户按“返回”按钮或旋转屏幕时。此外，DialogFragment 类还允许将对话框的 UI 作为嵌入式组件在较大 UI 中重复使用，就像传统 Fragment 一样

DialogFragment 类最初是通过 Android 3.0（API 11）添加的，如果想要使应用可以在运行 Android 1.6 或更高版本的设备上使用 DialogFragment 以及各种其他 API，可以使用支持库附带的 DialogFragment 类（android.support.v4.app.DialogFragment）。如果应用支持的最低版本是 API 级别 11 或更高版本，则可使用 DialogFragment 的框架版本（android.app.DialogFragment）

一、基础用法

通过扩展 DialogFragment 类并在 onCreateDialog() 回调方法中创建 AlertDialog

public class MyDialogFragment extends DialogFragment {@Overridepublic Dialog onCreateDialog(Bundle savedInstanceState) {AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());builder.setTitle("title").setMessage("message").setPositiveButton("确定", new DialogInterface.OnClickListener() {public void onClick(DialogInterface dialog, int id) {}}).setNegativeButton("取消", new DialogInterface.OnClickListener() {public void onClick(DialogInterface dialog, int id) {}});return builder.create();}}

之后，当创建此类的实例并调用该对象上的 show() 方法时，就可以显示出对话框了
这是 DialogFragment 最基础用法，之后会介绍几种不同的样式

二、包含两个按钮的对话框

在 ButtonDialogFragment 类中重载 show() 方法，传入所有需要的参数，并调用 DialogFragment 类本身的 show(FragmentManager manager, String tag) 方法，从而显示对话框。”tag” 参数是系统用于保存片段状态并在必要时进行恢复的唯一标记名称，该标记还允许通过调用 findFragmentByTag() 获取片段的句柄

/*** Created by 叶应是叶 on 2017/2/23.*/public class ButtonDialogFragment extends DialogFragment {private DialogInterface.OnClickListener positiveCallback;private DialogInterface.OnClickListener negativeCallback;private String title;private String message;public void show(String title, String message, DialogInterface.OnClickListener positiveCallback,DialogInterface.OnClickListener negativeCallback, FragmentManager fragmentManager) {this.title = title;this.message = message;this.positiveCallback = positiveCallback;this.negativeCallback = negativeCallback;show(fragmentManager, "ButtonDialogFragment");}@Overridepublic Dialog onCreateDialog(Bundle savedInstanceState) {AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());builder.setTitle(title);builder.setMessage(message);builder.setPositiveButton("确定", positiveCallback);builder.setNegativeButton("取消", negativeCallback);return builder.create();}}

之后，提供调用方法

public void showButtonDialogFragment(View view) {ButtonDialogFragment buttonDialogFragment = new ButtonDialogFragment();buttonDialogFragment.show("Hi,你好", "叶应是叶", new DialogInterface.OnClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which) {Toast.makeText(MainActivity.this, "点击了确定 " + which, Toast.LENGTH_SHORT).show();}}, new DialogInterface.OnClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which) {Toast.makeText(MainActivity.this, "点击了取消 " + which, Toast.LENGTH_SHORT).show();}}, getFragmentManager());}

运行效果
这里写图片描述

三、包含一个中性按钮的对话框

思路类似，对话框包含一个中性按钮

/*** Created by ZY on 2017/2/23.*/public class NeutralDialogFragment extends DialogFragment {private DialogInterface.OnClickListener neutralCallback;private String title;private String message;private String hint;public void show(String title, String message, String hint, DialogInterface.OnClickListener neutralCallback,FragmentManager fragmentManager) {this.title = title;this.message = message;this.hint = hint;this.neutralCallback = neutralCallback;show(fragmentManager, "NeutralDialogFragment");}@Overridepublic Dialog onCreateDialog(Bundle savedInstanceState) {AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());builder.setTitle(title);builder.setMessage(message);builder.setNeutralButton(hint, neutralCallback);return builder.create();}}

提供调用方法

    public void showNeutralDialogFragment(View view) {NeutralDialogFragment neutralDialogFragment = new NeutralDialogFragment();neutralDialogFragment.show("Hi,你好", "叶应是叶", "确定~", new DialogInterface.OnClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which) {Toast.makeText(MainActivity.this, "点击了按钮 " + which, Toast.LENGTH_SHORT).show();}}, getFragmentManager());}

运行效果
这里写图片描述

四、列表对话框

/*** Created by ZY on 2017/2/23.*/public class ItemsDialogFragment extends DialogFragment {private String title;private String[] items;private DialogInterface.OnClickListener onClickListener;public void show(String title, String[] items, DialogInterface.OnClickListener onClickListener,FragmentManager fragmentManager) {this.title = title;this.items = items;this.onClickListener = onClickListener;show(fragmentManager, "ItemsDialogFragment");}@Overridepublic Dialog onCreateDialog(Bundle savedInstanceState) {AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());builder.setTitle(title).setItems(items, onClickListener);return builder.create();}}

提供调用方法

public void showItemsDialogFragment(View view) {ItemsDialogFragment itemsDialogFragment = new ItemsDialogFragment();String[] items = {"Hi", "Hello", "叶"};itemsDialogFragment.show("Hi,你好", items, new DialogInterface.OnClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which) {Toast.makeText(MainActivity.this, "点击了第 " + (which + 1) + " 个选项", Toast.LENGTH_SHORT).show();}}, getFragmentManager());}

运行效果
这里写图片描述

五、多项选择对话框

/*** Created by ZY on 2017/2/23.*/public class MultiChoiceDialogFragment extends DialogFragment {private String title;private String[] items;private DialogInterface.OnMultiChoiceClickListener onMultiChoiceClickListener;private DialogInterface.OnClickListener positiveCallback;public void show(String title, String[] items, DialogInterface.OnMultiChoiceClickListener onMultiChoiceClickListener,DialogInterface.OnClickListener positiveCallback, FragmentManager fragmentManager) {this.title = title;this.items = items;this.onMultiChoiceClickListener = onMultiChoiceClickListener;this.positiveCallback = positiveCallback;show(fragmentManager, "MultiChoiceDialogFragment");}@Overridepublic Dialog onCreateDialog(Bundle savedInstanceState) {AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());builder.setTitle(title).setMultiChoiceItems(items, null, onMultiChoiceClickListener).setPositiveButton("确定", positiveCallback);return builder.create();}}

提供调用方法

public void showMultiChoiceDialogFragment(View view) {MultiChoiceDialogFragment multiChoiceDialogFragment = new MultiChoiceDialogFragment();final String[] items = {"Hi", "Hello", "叶"};final List<Integer> integerList = new ArrayList<>();multiChoiceDialogFragment.show("Hi,你好", items, new DialogInterface.OnMultiChoiceClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which, boolean isChecked) {if (isChecked) {integerList.add(which);} else {integerList.remove(which);}}}, new DialogInterface.OnClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which) {String hint = "";for (int i = 0; i < integerList.size(); i++) {hint = items[integerList.get(i)] + hint;}Toast.makeText(MainActivity.this, hint, Toast.LENGTH_SHORT).show();}}, getFragmentManager());}

运行效果
这里写图片描述

六、单项选择对话框

/*** Created by ZY on 2017/2/23.*/public class SingleChoiceDialogFragment extends DialogFragment {private String title;private String[] items;private DialogInterface.OnClickListener onClickListener;private DialogInterface.OnClickListener positiveCallback;public void show(String title, String[] items, DialogInterface.OnClickListener onClickListener,DialogInterface.OnClickListener positiveCallback, FragmentManager fragmentManager) {this.title = title;this.items = items;this.onClickListener = onClickListener;this.positiveCallback = positiveCallback;show(fragmentManager, "SingleChoiceDialogFragment");}@Overridepublic Dialog onCreateDialog(Bundle savedInstanceState) {AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());builder.setTitle(title).setSingleChoiceItems(items, 0, onClickListener).setPositiveButton("确定", positiveCallback);return builder.create();}}

提供调用方法

  private int index;public void showSingleChoiceDialogFragment(View view) {SingleChoiceDialogFragment singleChoiceDialogFragment = new SingleChoiceDialogFragment();String[] items = {"Hi", "Hello", "叶"};singleChoiceDialogFragment.show("Hi,你好", items, new DialogInterface.OnClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which) {index = which;}}, new DialogInterface.OnClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which) {Toast.makeText(MainActivity.this, "选择了第" + (index + 1) + "项", Toast.LENGTH_SHORT).show();}}, getFragmentManager());}

运行效果
这里写图片描述

七、自定义对话框

可以通过创建一个自定义布局，然后调用 AlertDialog.Builder 对象上的 setView() 方法将其添加到 AlertDialog 中，从而让对话框拥有自定义样式

首先自定义布局

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"android:layout_width="wrap_content"android:layout_height="wrap_content"android:orientation="vertical"><ImageView
        android:layout_width="match_parent"android:layout_height="64dp"android:background="#FFFFBB33"android:contentDescription="@string/app_name"android:scaleType="fitXY"android:src="@drawable/head" /><EditText
        android:id="@+id/username"android:layout_width="match_parent"android:layout_height="wrap_content"android:layout_marginBottom="4dp"android:layout_marginLeft="4dp"android:layout_marginRight="4dp"android:layout_marginTop="16dp"android:hint="用户名"android:inputType="textEmailAddress" /><EditText
        android:id="@+id/password"android:layout_width="match_parent"android:layout_height="wrap_content"android:layout_marginBottom="16dp"android:layout_marginLeft="4dp"android:layout_marginRight="4dp"android:layout_marginTop="4dp"android:fontFamily="sans-serif"android:hint="密码"android:inputType="textPassword" /></LinearLayout>

在 DialogFragment 的 onCreateDialog() 方法中加载自定义布局，并添加到 AlertDialog.Builder 中
此外，自定义一个接口 Callback，用于获取用户名与密码

/*** Created by ZY on 2017/2/23.*/public class ViewDialogFragment extends DialogFragment {public interface Callback {void onClick(String userName, String password);}private Callback callback;public void show(FragmentManager fragmentManager) {show(fragmentManager, "ViewDialogFragment");}@Overridepublic Dialog onCreateDialog(Bundle savedInstanceState) {AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());LayoutInflater inflater = getActivity().getLayoutInflater();final View view = inflater.inflate(R.layout.dialog_signin, null);builder.setView(view).setPositiveButton("确定", new DialogInterface.OnClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which) {if (callback != null) {EditText et_userName = (EditText) view.findViewById(R.id.username);EditText et_password = (EditText) view.findViewById(R.id.password);callback.onClick(et_userName.getText().toString(), et_password.getText().toString());}}});return builder.create();}@Overridepublic void onAttach(Context context) {super.onAttach(context);if (context instanceof Callback) {callback = (Callback) context;} else {throw new RuntimeException(context.toString() + " must implement Callback");}}@Overridepublic void onDestroy() {super.onDestroy();callback = null;}
}

令 Activity 实现 Callbak 接口

public class MainActivity extends AppCompatActivity implements ViewDialogFragment.Callback {@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);}public void showViewDialogFragment(View view) {ViewDialogFragment viewDialogFragment = new ViewDialogFragment();viewDialogFragment.show(getFragmentManager());}@Overridepublic void onClick(String userName, String password) {Toast.makeText(MainActivity.this, "用户名: " + userName + " 密码: " + password, Toast.LENGTH_SHORT).show();}}