DialogFragment_dialogfragment未展示-优快云博客

            <p>转载请标明出处：<a href="http://blog.youkuaiyun.com/lmj623565791/article/details/37815413" target="_blank">http://blog.youkuaiyun.com/lmj623565791/article/details/37815413</a></p><h6>1、 概述</h6>DialogFragment在android 3.0时被引入。是一种特殊的Fragment，用于在Activity的内容之上展示一个模态的对话框。典型的用于：展示警告框，输入框，确认框等等。<br>在DialogFragment产生之前，我们创建对话框：一般采用AlertDialog和Dialog。注：官方不推荐直接使用Dialog创建对话框。<br><h6>2、 好处与用法</h6>使用DialogFragment来管理对话框，当旋转屏幕和按下后退键时可以更好的管理其声明周期，它和Fragment有着基本一致的声明周期。且DialogFragment也允许开发者把Dialog作为内嵌的组件进行重用，类似Fragment（可以在大屏幕和小屏幕显示出不同的效果）。上面会通过例子展示这些好处~<br><p>使用DialogFragment至少需要实现onCreateView或者onCreateDIalog方法。onCreateView即使用定义的xml布局文件展示Dialog。onCreateDialog即利用AlertDialog或者Dialog创建出Dialog。</p><h6>3、 重写onCreateView创建Dialog</h6><p>a)布局文件，我们创建一个设置名称的布局文件：</p><p></p><div class="dp-highlighter bg_html"><div class="bar"><div class="tools"><b>[html]</b> <a href="#" class="ViewSource" title="view plain" onclick="dp.sh.Toolbar.Command('ViewSource',this);return false;">view plain</a><span data-mod="popu_168"> <a href="#" class="CopyToClipboard" title="copy" onclick="dp.sh.Toolbar.Command('CopyToClipboard',this);return false;">copy</a><div style="position: absolute; left: 582px; top: 738px; width: 16px; height: 16px; z-index: 99;"><embed id="ZeroClipboardMovie_1" src="https://csdnimg.cn/public/highlighter/ZeroClipboard.swf" loop="false" menu="false" quality="best" bgcolor="#ffffff" name="ZeroClipboardMovie_1" allowscriptaccess="always" allowfullscreen="false" type="application/x-shockwave-flash" pluginspage="http://www.macromedia.com/go/getflashplayer" flashvars="id=1&amp;width=16&amp;height=16" wmode="transparent" width="16" height="16" align="middle"></div><div style="position: absolute; left: 582px; top: 738px; width: 16px; height: 16px; z-index: 99;"><embed id="ZeroClipboardMovie_14" src="https://csdnimg.cn/public/highlighter/ZeroClipboard.swf" loop="false" menu="false" quality="best" bgcolor="#ffffff" name="ZeroClipboardMovie_14" allowscriptaccess="always" allowfullscreen="false" type="application/x-shockwave-flash" pluginspage="http://www.macromedia.com/go/getflashplayer" flashvars="id=14&amp;width=16&amp;height=16" wmode="transparent" width="16" height="16" align="middle"></div></span><span data-mod="popu_169"> <a href="#" class="PrintSource" title="print" onclick="dp.sh.Toolbar.Command('PrintSource',this);return false;">print</a></span><a href="#" class="About" title="?" onclick="dp.sh.Toolbar.Command('About',this);return false;">?</a></div></div><ol start="1" class="dp-xml"><li class="alt"><span><span class="tag">&lt;?</span><span class="tag-name">xml</span><span>&nbsp;</span><span class="attribute">version</span><span>=</span><span class="attribute-value">"1.0"</span><span>&nbsp;</span><span class="attribute">encoding</span><span>=</span><span class="attribute-value">"utf-8"</span><span class="tag">?&gt;</span><span>&nbsp;&nbsp;</span></span></li><li class=""><span><span class="tag">&lt;</span><span class="tag-name">RelativeLayout</span><span>&nbsp;</span><span class="attribute">xmlns:android</span><span>=</span><span class="attribute-value">"http://schemas.android.com/apk/res/android"</span><span>&nbsp;&nbsp;</span></span></li><li class="alt"><span>&nbsp;&nbsp;&nbsp;&nbsp;<span class="attribute">android:layout_width</span><span>=</span><span class="attribute-value">"wrap_content"</span><span>&nbsp;&nbsp;</span></span></li><li class=""><span>&nbsp;&nbsp;&nbsp;&nbsp;<span class="attribute">android:layout_height</span><span>=</span><span class="attribute-value">"wrap_content"</span><span>&nbsp;</span><span class="tag">&gt;</span><span>&nbsp;&nbsp;</span></span></li><li class="alt"><span>&nbsp;&nbsp;</span></li><li class=""><span>&nbsp;&nbsp;&nbsp;&nbsp;<span class="tag">&lt;</span><span class="tag-name">TextView</span><span>&nbsp;&nbsp;</span></span></li><li class="alt"><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="attribute">android:id</span><span>=</span><span class="attribute-value">"@+id/id_label_your_name"</span><span>&nbsp;&nbsp;</span></span></li><li class=""><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="attribute">android:layout_width</span><span>=</span><span class="attribute-value">"wrap_content"</span><span>&nbsp;&nbsp;</span></span></li><li class="alt"><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="attribute">android:layout_height</span><span>=</span><span class="attribute-value">"32dp"</span><span>&nbsp;&nbsp;</span></span></li><li class=""><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="attribute">android:gravity</span><span>=</span><span class="attribute-value">"center_vertical"</span><span>&nbsp;&nbsp;</span></span></li><li class="alt"><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="attribute">android:text</span><span>=</span><span class="attribute-value">"Your&nbsp;name:"</span><span>&nbsp;</span><span class="tag">/&gt;</span><span>&nbsp;&nbsp;</span></span></li><li class=""><span>&nbsp;&nbsp;</span></li><li class="alt"><span>&nbsp;&nbsp;&nbsp;&nbsp;<span class="tag">&lt;</span><span class="tag-name">EditText</span><span>&nbsp;&nbsp;</span></span></li><li class=""><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="attribute">android:id</span><span>=</span><span class="attribute-value">"@+id/id_txt_your_name"</span><span>&nbsp;&nbsp;</span></span></li><li class="alt"><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="attribute">android:layout_width</span><span>=</span><span class="attribute-value">"match_parent"</span><span>&nbsp;&nbsp;</span></span></li><li class=""><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="attribute">android:layout_height</span><span>=</span><span class="attribute-value">"wrap_content"</span><span>&nbsp;&nbsp;</span></span></li><li class="alt"><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="attribute">android:layout_toRightOf</span><span>=</span><span class="attribute-value">"@id/id_label_your_name"</span><span>&nbsp;&nbsp;</span></span></li><li class=""><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="attribute">android:imeOptions</span><span>=</span><span class="attribute-value">"actionDone"</span><span>&nbsp;&nbsp;</span></span></li><li class="alt"><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="attribute">android:inputType</span><span>=</span><span class="attribute-value">"text"</span><span>&nbsp;</span><span class="tag">/&gt;</span><span>&nbsp;&nbsp;</span></span></li><li class=""><span>&nbsp;&nbsp;</span></li><li class="alt"><span>&nbsp;&nbsp;&nbsp;&nbsp;<span class="tag">&lt;</span><span class="tag-name">Button</span><span>&nbsp;&nbsp;</span></span></li><li class=""><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="attribute">android:id</span><span>=</span><span class="attribute-value">"@+id/id_sure_edit_name"</span><span>&nbsp;&nbsp;</span></span></li><li class="alt"><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="attribute">android:layout_width</span><span>=</span><span class="attribute-value">"wrap_content"</span><span>&nbsp;&nbsp;</span></span></li><li class=""><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="attribute">android:layout_height</span><span>=</span><span class="attribute-value">"wrap_content"</span><span>&nbsp;&nbsp;</span></span></li><li class="alt"><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="attribute">android:layout_alignParentRight</span><span>=</span><span class="attribute-value">"true"</span><span>&nbsp;&nbsp;</span></span></li><li class=""><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="attribute">android:layout_below</span><span>=</span><span class="attribute-value">"@id/id_txt_your_name"</span><span>&nbsp;&nbsp;</span></span></li><li class="alt"><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="attribute">android:text</span><span>=</span><span class="attribute-value">"ok"</span><span>&nbsp;</span><span class="tag">/&gt;</span><span>&nbsp;&nbsp;</span></span></li><li class=""><span>&nbsp;&nbsp;</span></li><li class="alt"><span><span class="tag">&lt;/</span><span class="tag-name">RelativeLayout</span><span class="tag">&gt;</span><span>&nbsp;&nbsp;</span></span></li></ol></div><pre class="html" name="code" style="display: none;">&lt;?xml version="1.0" encoding="utf-8"?&gt;

&lt;TextView
    android:id="@+id/id_label_your_name"
    android:layout_width="wrap_content"
    android:layout_height="32dp"
    android:gravity="center_vertical"
    android:text="Your name:" /&gt;

&lt;EditText
    android:id="@+id/id_txt_your_name"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_toRightOf="@id/id_label_your_name"
    android:imeOptions="actionDone"
    android:inputType="text" /&gt;

&lt;Button
    android:id="@+id/id_sure_edit_name"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentRight="true"
    android:layout_below="@id/id_txt_your_name"
    android:text="ok" /&gt;

</RelativeLayout>
b)继承DialogFragment，重写onCreateView方法

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package com.example.zhy_dialogfragment;
import android.app.DialogFragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
public class EditNameDialogFragment extends DialogFragment
{
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState)
{
View view = inflater.inflate(R.layout.fragment_edit_name, container);
return view;
}
}

package com.example.zhy_dialogfragment;

import android.app.DialogFragment; 

import android.os.Bundle; 

import android.view.LayoutInflater; 

import android.view.View; 

import android.view.ViewGroup;

public class EditNameDialogFragment extends DialogFragment 

{

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState)
{
    View view = inflater.inflate(R.layout.fragment_edit_name, container);
    return view;
}

}

c)测试运行：

Main方法中调用：

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public void showEditDialog(View view)
{
EditNameDialogFragment editNameDialog = new EditNameDialogFragment();
editNameDialog.show(getFragmentManager(), ”EditNameDialog”);
}

public void showEditDialog(View view) 

    { 

        EditNameDialogFragment editNameDialog = new EditNameDialogFragment(); 

        editNameDialog.show(getFragmentManager(), "EditNameDialog"); 

    }

效果图：

可以看到，对话框成功创建并显示出来，不过默认对话框有个讨厌的标题，我们怎么去掉呢：可以在onCreateView中调用getDialog().requestWindowFeature(Window.FEATURE_NO_TITLE);即可去掉。即：

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public class EditNameDialogFragment extends DialogFragment
{
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState)
{
getDialog().requestWindowFeature(Window.FEATURE_NO_TITLE);
View view = inflater.inflate(R.layout.fragment_edit_name, container);
return view;
}
}

public class EditNameDialogFragment extends DialogFragment 

{

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState)
{
    getDialog().requestWindowFeature(Window.FEATURE_NO_TITLE);
    View view = inflater.inflate(R.layout.fragment_edit_name, container);
    return view;
}

}

效果图：

很完美的去掉了讨厌的标题。

4、重写onCreateDialog创建Dialog

在onCreateDialog中一般可以使用AlertDialog或者Dialog创建对话框，不过既然google不推荐直接使用Dialog，我们就使用AlertDialog来创建一个登录的对话框。

a)布局文件

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<?xml version=“1.0” encoding=“utf-8”?>
<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=“center”
android:src=“@drawable/title” />
<EditText
android:id=“@+id/id_txt_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=“input username”
android:inputType=“textEmailAddress” />
<EditText
android:id=“@+id/id_txt_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=“input password”
android:inputType=“textPassword” />
</LinearLayout>

<?xml version="1.0" encoding="utf-8"?> 

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 

    android:layout_width="wrap_content" 

    android:layout_height="wrap_content" 

    android:orientation="vertical" >

&lt;ImageView
    android:layout_width="match_parent"
    android:layout_height="64dp"
    android:background="#FFFFBB33"
    android:contentDescription="@string/app_name"
    android:scaleType="center"
    android:src="@drawable/title" /&gt;

&lt;EditText
    android:id="@+id/id_txt_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="input username"
    android:inputType="textEmailAddress" /&gt;

&lt;EditText
    android:id="@+id/id_txt_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="input password"
    android:inputType="textPassword" /&gt;

</LinearLayout>

b)继承DialogFragment重写onCreateDialog方法

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package com.example.zhy_dialogfragment;
import android.app.AlertDialog;
import android.app.Dialog;
import android.app.DialogFragment;
import android.content.DialogInterface;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.EditText;
public class LoginDialogFragment extends DialogFragment
{
@Override
public Dialog onCreateDialog(Bundle savedInstanceState)
{
AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
// Get the layout inflater
LayoutInflater inflater = getActivity().getLayoutInflater();
View view = inflater.inflate(R.layout.fragment_login_dialog, null);
// Inflate and set the layout for the dialog
// Pass null as the parent view because its going in the dialog layout
builder.setView(view)
// Add action buttons
.setPositiveButton(”Sign in”,
new DialogInterface.OnClickListener()
{
@Override
public void onClick(DialogInterface dialog, int id)
{
}
}).setNegativeButton(”Cancel”, null);
return builder.create();
}
}

package com.example.zhy_dialogfragment;

import android.app.AlertDialog; 

import android.app.Dialog; 

import android.app.DialogFragment; 

import android.content.DialogInterface; 

import android.os.Bundle; 

import android.view.LayoutInflater; 

import android.view.View; 

import android.view.ViewGroup; 

import android.widget.EditText;

public class LoginDialogFragment extends DialogFragment 

{

@Override
public Dialog onCreateDialog(Bundle savedInstanceState)
{
    AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
    // Get the layout inflater
    LayoutInflater inflater = getActivity().getLayoutInflater();
    View view = inflater.inflate(R.layout.fragment_login_dialog, null);
    // Inflate and set the layout for the dialog
    // Pass null as the parent view because its going in the dialog layout
    builder.setView(view)
            // Add action buttons
            .setPositiveButton("Sign in",
                    new DialogInterface.OnClickListener()
                    {
                        @Override
                        public void onClick(DialogInterface dialog, int id)
                        {
                        }
                    }).setNegativeButton("Cancel", null);
    return builder.create();
}

}

c)调用

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public void showLoginDialog(View view)
{
LoginDialogFragment dialog = new LoginDialogFragment();
dialog.show(getFragmentManager(), ”loginDialog”);
}

public void showLoginDialog(View view) 

    { 

        LoginDialogFragment dialog = new LoginDialogFragment(); 

        dialog.show(getFragmentManager(), "loginDialog"); 

    }

效果图：

可以看到通过重写onCreateDialog同样可以实现创建对话框，效果还是很nice的。

5、传递数据给Activity

从dialog传递数据给Activity，可以使用“fragment interface pattern”的方式，下面通过一个改造上面的登录框来展示这种模式。

改动比较小，直接贴代码了：

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package com.example.zhy_dialogfragment;
import android.app.AlertDialog;
import android.app.Dialog;
import android.app.DialogFragment;
import android.content.DialogInterface;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.EditText;
public class LoginDialogFragment extends DialogFragment
{
private EditText mUsername;
private EditText mPassword;
public interface LoginInputListener
{
void onLoginInputComplete(String username, String password);
}
@Override
public Dialog onCreateDialog(Bundle savedInstanceState)
{
AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
// Get the layout inflater
LayoutInflater inflater = getActivity().getLayoutInflater();
View view = inflater.inflate(R.layout.fragment_login_dialog, null);
mUsername = (EditText) view.findViewById(R.id.id_txt_username);
mPassword = (EditText) view.findViewById(R.id.id_txt_password);
// Inflate and set the layout for the dialog
// Pass null as the parent view because its going in the dialog layout
builder.setView(view)
// Add action buttons
.setPositiveButton(”Sign in”,
new DialogInterface.OnClickListener()
{
@Override
public void onClick(DialogInterface dialog, int id)
{
LoginInputListener listener = (LoginInputListener) getActivity();
listener.onLoginInputComplete(mUsername
.getText().toString(), mPassword
.getText().toString());
}
}).setNegativeButton(”Cancel”, null);
return builder.create();
}
}

package com.example.zhy_dialogfragment;

import android.app.AlertDialog; 

import android.app.Dialog; 

import android.app.DialogFragment; 

import android.content.DialogInterface; 

import android.os.Bundle; 

import android.view.LayoutInflater; 

import android.view.View; 

import android.view.ViewGroup; 

import android.widget.EditText;

public class LoginDialogFragment extends DialogFragment 

{ 

    private EditText mUsername; 

    private EditText mPassword;

public interface LoginInputListener
{
    void onLoginInputComplete(String username, String password);
}

@Override
public Dialog onCreateDialog(Bundle savedInstanceState)
{
    AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
    // Get the layout inflater
    LayoutInflater inflater = getActivity().getLayoutInflater();
    View view = inflater.inflate(R.layout.fragment_login_dialog, null);
    mUsername = (EditText) view.findViewById(R.id.id_txt_username);
    mPassword = (EditText) view.findViewById(R.id.id_txt_password);
    // Inflate and set the layout for the dialog
    // Pass null as the parent view because its going in the dialog layout
    builder.setView(view)
            // Add action buttons
            .setPositiveButton("Sign in",
                    new DialogInterface.OnClickListener()
                    {
                        @Override
                        public void onClick(DialogInterface dialog, int id)
                        {
                            LoginInputListener listener = (LoginInputListener) getActivity();
                            listener.onLoginInputComplete(mUsername
                                    .getText().toString(), mPassword
                                    .getText().toString());
                        }
                    }).setNegativeButton("Cancel", null);
    return builder.create();
}

}

拿到username和password的引用，在点击登录的时候，把activity强转为我们自定义的接口：LoginInputListener，然后将用户输入的数据返回。

MainActivity中需要实现我们的接口LoginInputListener，实现我们的方法，就可以实现当用户点击登陆时，获得我们的帐号密码了：

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c) MainActivity
package com.example.zhy_dialogfragment;
import com.example.zhy_dialogfragment.LoginDialogFragment.LoginInputListener;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.Toast;
public class MainActivity extends Activity implements LoginInputListener
{
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void showLoginDialog(View view)
{
LoginDialogFragment dialog = new LoginDialogFragment();
dialog.show(getFragmentManager(), ”loginDialog”);
}
@Override
public void onLoginInputComplete(String username, String password)
{
Toast.makeText(this, “帐号：” + username + “, 密码 :” + password,
Toast.LENGTH_SHORT).show();
}
}

c)  MainActivity 

package com.example.zhy_dialogfragment;

import com.example.zhy_dialogfragment.LoginDialogFragment.LoginInputListener;

import android.app.Activity; 

import android.app.AlertDialog; 

import android.content.DialogInterface; 

import android.os.Bundle; 

import android.view.LayoutInflater; 

import android.view.View; 

import android.widget.Toast;

public class MainActivity extends Activity implements LoginInputListener 

{

@Override
protected void onCreate(Bundle savedInstanceState)
{
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
}



public void showLoginDialog(View view)
{
    LoginDialogFragment dialog = new LoginDialogFragment();
    dialog.show(getFragmentManager(), "loginDialog");

}

@Override
public void onLoginInputComplete(String username, String password)
{
    Toast.makeText(this, "帐号：" + username + ",  密码 :" + password,
            Toast.LENGTH_SHORT).show();
}

}

效果：

6、DialogFragment做屏幕适配

我们希望，一个对话框在大屏幕上以对话框的形式展示，而小屏幕上则直接嵌入当前的Actvity中。这种效果的对话框，只能通过重写onCreateView实现。下面我们利用上面的EditNameDialogFragment来显示。

EditNameDialogFragment我们已经编写好了，直接在MainActivity中写调用

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public void showDialogInDifferentScreen(View view)
{
FragmentManager fragmentManager = getFragmentManager();
EditNameDialogFragment newFragment = new EditNameDialogFragment();
boolean mIsLargeLayout = getResources().getBoolean(R.bool.large_layout) ;
Log.e(”TAG”, mIsLargeLayout+“”);
if (mIsLargeLayout )
{
// The device is using a large layout, so show the fragment as a
// dialog
newFragment.show(fragmentManager, ”dialog”);
} else
{
// The device is smaller, so show the fragment fullscreen
FragmentTransaction transaction = fragmentManager
.beginTransaction();
// For a little polish, specify a transition animation
transaction
.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
// To make it fullscreen, use the ‘content’ root view as the
// container
// for the fragment, which is always the root view for the activity
transaction.replace(R.id.id_ly, newFragment)
.commit();
}
}

public void showDialogInDifferentScreen(View view) 

    { 

        FragmentManager fragmentManager = getFragmentManager(); 

        EditNameDialogFragment newFragment = new EditNameDialogFragment();

    boolean mIsLargeLayout = getResources().getBoolean(R.bool.large_layout) ;
    Log.e("TAG", mIsLargeLayout+"");
    if (mIsLargeLayout )
    {
        // The device is using a large layout, so show the fragment as a
        // dialog
        newFragment.show(fragmentManager, "dialog");
    } else
    {
        // The device is smaller, so show the fragment fullscreen
        FragmentTransaction transaction = fragmentManager
                .beginTransaction();
        // For a little polish, specify a transition animation
        transaction
                .setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
        // To make it fullscreen, use the 'content' root view as the
        // container
        // for the fragment, which is always the root view for the activity
        transaction.replace(R.id.id_ly, newFragment)
                .commit();
    }
}</pre><br>可以看到，我们通过读取R.bool.large_layout，然后根据得到的布尔值，如果是大屏幕则直接以对话框显示，如果是小屏幕则嵌入我们的Activity布局中<p></p><p>这个R.bool.large_layout是我们定义的资源文件：</p><p>在默认的values下新建一个bools.xml</p><p></p><div class="dp-highlighter bg_html"><div class="bar"><div class="tools"><b>[html]</b> <a href="#" class="ViewSource" title="view plain" onclick="dp.sh.Toolbar.Command('ViewSource',this);return false;">view plain</a><span data-mod="popu_168"> <a href="#" class="CopyToClipboard" title="copy" onclick="dp.sh.Toolbar.Command('CopyToClipboard',this);return false;">copy</a><div style="position: absolute; left: 582px; top: 9840px; width: 16px; height: 16px; z-index: 99;"><embed id="ZeroClipboardMovie_11" src="https://csdnimg.cn/public/highlighter/ZeroClipboard.swf" loop="false" menu="false" quality="best" bgcolor="#ffffff" name="ZeroClipboardMovie_11" allowscriptaccess="always" allowfullscreen="false" type="application/x-shockwave-flash" pluginspage="http://www.macromedia.com/go/getflashplayer" flashvars="id=11&amp;width=16&amp;height=16" wmode="transparent" width="16" height="16" align="middle"></div><div style="position: absolute; left: 582px; top: 9840px; width: 16px; height: 16px; z-index: 99;"><embed id="ZeroClipboardMovie_24" src="https://csdnimg.cn/public/highlighter/ZeroClipboard.swf" loop="false" menu="false" quality="best" bgcolor="#ffffff" name="ZeroClipboardMovie_24" allowscriptaccess="always" allowfullscreen="false" type="application/x-shockwave-flash" pluginspage="http://www.macromedia.com/go/getflashplayer" flashvars="id=24&amp;width=16&amp;height=16" wmode="transparent" width="16" height="16" align="middle"></div></span><span data-mod="popu_169"> <a href="#" class="PrintSource" title="print" onclick="dp.sh.Toolbar.Command('PrintSource',this);return false;">print</a></span><a href="#" class="About" title="?" onclick="dp.sh.Toolbar.Command('About',this);return false;">?</a></div></div><ol start="1" class="dp-xml"><li class="alt"><span><span class="tag">&lt;?</span><span class="tag-name">xml</span><span>&nbsp;</span><span class="attribute">version</span><span>=</span><span class="attribute-value">"1.0"</span><span>&nbsp;</span><span class="attribute">encoding</span><span>=</span><span class="attribute-value">"utf-8"</span><span class="tag">?&gt;</span><span>&nbsp;&nbsp;</span></span></li><li class=""><span><span class="tag">&lt;</span><span class="tag-name">resources</span><span class="tag">&gt;</span><span>&nbsp;&nbsp;</span></span></li><li class="alt"><span>&nbsp;&nbsp;</span></li><li class=""><span>&nbsp;&nbsp;&nbsp;&nbsp;<span class="tag">&lt;</span><span class="tag-name">bool</span><span>&nbsp;</span><span class="attribute">name</span><span>=</span><span class="attribute-value">"large_layout"</span><span class="tag">&gt;</span><span>false</span><span class="tag">&lt;/</span><span class="tag-name">bool</span><span class="tag">&gt;</span><span>&nbsp;&nbsp;</span></span></li><li class="alt"><span>&nbsp;&nbsp;</span></li><li class=""><span><span class="tag">&lt;/</span><span class="tag-name">resources</span><span class="tag">&gt;</span><span>&nbsp;&nbsp;</span></span></li></ol></div><pre class="html" name="code" style="display: none;">&lt;?xml version="1.0" encoding="utf-8"?&gt;

&lt;bool name="large_layout"&gt;false&lt;/bool&gt;

</resources>

然后在res下新建一个values-large，在values-large下再新建一个bools.xml

[html] view plain copy

print ?

<?xml version=“1.0” encoding=“utf-8”?>
<resources>
<bool name=“large_layout”>true</bool>
</resources>

<?xml version="1.0" encoding="utf-8"?> 

<resources>

&lt;bool name="large_layout"&gt;true&lt;/bool&gt;

</resources>

最后测试：

左边为模拟器，右边为我的手机~

7、屏幕旋转

当用户输入帐号密码时，忽然旋转了一下屏幕，帐号密码不见了~~~是不是会抓狂

传统的new AlertDialog在屏幕旋转时，第一不会保存用户输入的值，第二还会报异常，因为Activity销毁前不允许对话框未关闭。而通过DialogFragment实现的对话框则可以完全不必考虑旋转的问题。

我们直接把上面登录使用AlertDialog创建的登录框，拷贝到MainActivity中直接调用：

[java] view plain copy

print ?

public void showLoginDialogWithoutFragment(View view)
{
AlertDialog.Builder builder = new AlertDialog.Builder(this);
// Get the layout inflater
LayoutInflater inflater = this.getLayoutInflater();
// Inflate and set the layout for the dialog
// Pass null as the parent view because its going in the dialog layout
builder.setView(inflater.inflate(R.layout.fragment_login_dialog, null))
// Add action buttons
.setPositiveButton(”Sign in”,
new DialogInterface.OnClickListener()
{
@Override
public void onClick(DialogInterface dialog, int id)
{
// sign in the user …
}
}).setNegativeButton(”Cancel”, null).show();
}

public void showLoginDialogWithoutFragment(View view) 

    { 

        AlertDialog.Builder builder = new AlertDialog.Builder(this); 

        // Get the layout inflater 

        LayoutInflater inflater = this.getLayoutInflater();

    // Inflate and set the layout for the dialog
    // Pass null as the parent view because its going in the dialog layout
    builder.setView(inflater.inflate(R.layout.fragment_login_dialog, null))
            // Add action buttons
            .setPositiveButton("Sign in",
                    new DialogInterface.OnClickListener()
                    {
                        @Override
                        public void onClick(DialogInterface dialog, int id)
                        {
                            // sign in the user ...
                        }
                    }).setNegativeButton("Cancel", null).show();
}

下面我分别点击两种方式创建的登录框，看效果图：