安卓-从另一个片段中启动片段 C#[英] Android - Start Fragemnt from another Fragment C#

问题描述

I know this question has been asked too much here but i ahve tried every solution out there to open a fragment from another fragment and no one worked for me.

Fragment1.cs

public override View OnCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
    base.OnCreate(savedInstanceState);
    View view = inflater.Inflate(Resource.Layout.my_layout, container, false);
    return view;
    add.Click += delegate
        {
            Fragment2 fragment2 = new Fragment2();
            FragmentTransaction ft = FragmentManager.BeginTransaction();
            ft.Replace(Resource.Id.content_frame, fragment2);
            ft.Commit();
         };
}

my_layout

 <?xml version="1.0" encoding="utf-8"?>
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/content_frame">
<TextView
    android:text="Text"
    android:layout_width="match_parent"
    android:layout_height="70dp"
    android:id="@+id/total"
    android:textAlignment="center"
    android:textSize="30dp" />
<TextView
    android:text="Text"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/textchangevalue"
    android:textSize="33dip"
    android:textStyle="bold" />
<Button
    android:text="UPDATE"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:id="@+id/updatebtn" />
 <Button
    android:text="ADD"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:id="@+id/addbtn" />
 <ListView
    android:minWidth="25px"
    android:minHeight="25px"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/portfoliolist"
    android:clickable="true" />

Fragment2.cs

public override View OnCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
    {
        base.OnCreate(savedInstanceState);
        View view = inflater.Inflate(Resource.Layout.fragment_lay, container, false);

        TextView txt = view.FindViewById<TextView>(Resource.Id.textView1);
        Button btn = view.FindViewById<Button>(Resource.Id.button1);
        listView = view.FindViewById<ListView>(Resource.Id.listView1);
        Toast.MakeText(Activity, "Fragment2 started", ToastLength.Short).Show();
        return view;
       }

When I run the app, and click the add button nothing is happening. Why is that ? I have tried to change the layout of the Fragment1 by putting instead of <LinearLayout> a <FrameLayout> but also disn't worked. Please help me to find a solution.

EDIT: I have put a toast message in the Fragment2 and when I click the add button in the fragment1, the toast message (which is in the fragment2) is showing which means that the fragment2 is starting fine but it's layout is not showing on the screen.

推荐答案

You need a FrameLayout to contain your LinearLayout:

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/content_frame">
  <LinearLayout
android:id="@+id/ll"
      android:orientation="vertical"
      android:layout_width="match_parent"
      android:layout_height="match_parent">


    <TextView
        android:text="Text"
        android:layout_width="match_parent"
        android:layout_height="70dp"
        android:id="@+id/total"
        android:textAlignment="center"
        android:textSize="30dp" />
    <TextView
        android:text="Text"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/textchangevalue"
        android:textSize="33dip"
        android:textStyle="bold" />
    <Button
        android:text="UPDATE"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/updatebtn" />
    <Button
        android:text="ADD"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/addbtn" />
    <ListView
        android:minWidth="25px"
        android:minHeight="25px"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/portfoliolist"
        android:clickable="true" />
  </LinearLayout>
</FrameLayout>

And your code should be :

    public override View OnCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
    {
        // Use this to return your custom view for this Fragment
        var view = inflater.Inflate(Resource.Layout.my_layout, container, false);
        var ll = view.FindViewById<LinearLayout>(Resource.Id.ll);
        var bt = view.FindViewById(Resource.Id.addbtn);
        bt.Click+= delegate
        {
            Fragment2 fragment2 = new Fragment2();
            FragmentTransaction ft = FragmentManager.BeginTransaction();
            ft.Replace(Resource.Id.content_frame, fragment2);
            ft.Commit();
            ll.Visibility = ViewStates.Gone;
        };
        return view;
    }

You can refer to this to see why your fragment2 just top on it. I use ll.Visibility = ViewStates.Gone; to avoid it.

其他推荐答案

You have to attach your Click event to your button before return the view, and I think that you want to attach this event on your addbtn so you have to create the variable add before to attach this event

public override View OnCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
    base.OnCreate(savedInstanceState);
    View view = inflater.Inflate(Resource.Layout.my_layout, container, false);
    Button add = view.FindViewById<Button>(Resource.Id.addbtn);
    add.Click += delegate
    {
        Fragment2 fragment2 = new Fragment2();
        FragmentTransaction ft = FragmentManager.BeginTransaction();
        ft.Replace(Resource.Id.content_frame, fragment2);
        ft.Commit();
    };
    return view;
}

其他推荐答案

You can use the events instead:

public override View OnCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
    base.OnCreate(savedInstanceState);
    View view = inflater.Inflate(Resource.Layout.my_layout, container, false);
    Button add = view.FindViewById<Button>(Resource.Id.addbtn);
    add.Click += (object sender, EventArgs e) =>
    {
        Fragment2 fragment2 = new Fragment2();
        FragmentTransaction ft = FragmentManager.BeginTransaction();
        ft.Replace(Resource.Id.content_frame, fragment2);
        ft.Commit();
    };

    return view;
}