這是一個2部分問題。我所擁有的是3片段佈局,其中當用戶點擊另一個片段中找到的按鈕時,動態添加3'rd片段(FragmentC)。然後,它添加後,第三個片段有一個按鈕來最大化/最小化它。以編程方式顯示/隱藏碎片並更改visibility屬性
UPDATE:雙擊自動滾屏在年底SOLUTION
問題1:
我試圖改變充當容器的FrameLayout的可見性屬性對於第3個片段(R.id.fragment_C)。
代碼應該做的是生成另一個片段,最初有一個包含android:visibility =「gone」的XML。然後,當點擊一個按鈕時添加片段,並且可見性被設想變爲可見。
我知道這已被覆蓋之前,但經過4個小時的努力使其工作,我決定問我做錯了什麼。
問題2:
生成3'rd片段後,我有一個最小化/最大化按鈕的應該隱藏所述第一2個片段,並允許3'rd片段以填充屏幕。
問題是使用.setVisibility(View.GONE)時不會刪除前2個碎片的視圖。之前也已經介紹過,但我無法弄清楚爲什麼它在我的代碼中不起作用。
到目前爲止的代碼(抱歉,如果它以冗長,但我認爲這是更好地包括你們這些人的所有詳細信息):
main_activity.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:paddingLeft="0dp"
android:paddingRight="0dp"
android:orientation="vertical"
>
<FrameLayout
android:id="@+id/fragment_A"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:background="#CCCCCC"
>
</FrameLayout>
<FrameLayout
android:id="@+id/fragment_B"
android:layout_width="fill_parent"
android:layout_height="300dp"
android:layout_below="@id/fragment_A"
android:layout_centerHorizontal="true"
android:layout_marginTop="15dp"
android:background="#B4B4B4"
>
</FrameLayout>
<FrameLayout
android:id="@+id/fragment_C"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_below="@id/fragment_B"
android:layout_centerHorizontal="true"
android:layout_marginTop="0dp"
android:background="#A3A3A3"
android:visibility="gone"
>
</FrameLayout>
</RelativeLayout>
土地/ main_activity.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="horizontal"
android:paddingLeft="0dp"
android:paddingRight="0dp" >
<LinearLayout
android:id="@+id/fragments_container"
android:layout_width="fill_parent"
android:layout_height="200dp"
android:baselineAligned="false" >
<FrameLayout
android:id="@+id/fragment_A"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="0.5"
android:background="#CCCCCC" >
</FrameLayout>
<FrameLayout
android:id="@id/fragment_B"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="0.5"
android:background="#B4B4B4"
>
</FrameLayout>
</LinearLayout>
<FrameLayout
android:id="@+id/fragment_C"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_below="@id/fragment_container"
android:layout_centerHorizontal="true"
android:layout_marginTop="0dp"
android:background="#A3A3A3"
android:visibility="gone" >
</FrameLayout>
</RelativeLayout>
MainActivity.java
package com.example.android.fragments_proto.activity;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import com.example.android.fragments_proto.R;
import com.example.android.fragments_proto.fragment.GMC_DateSelectionFragment;
import com.example.android.fragments_proto.fragment.GMC_ProdUnitSelectionFragment;
public class MainActivity extends FragmentActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main_activity);
FragmentManager fm = getSupportFragmentManager();
Fragment fragmentA = fm.findFragmentById(R.id.fragment_A);
Fragment fragmentB = fm.findFragmentById(R.id.fragment_B);
if (fragmentA == null) {
FragmentTransaction ft = fm.beginTransaction();
ft.add(R.id.fragment_A, new FragmentA());
ft.commit();
}
if (fragmentB == null) {
FragmentTransaction ft = fm.beginTransaction();
ft.add(R.id.fragment_B, new FragmentB());
ft.commit();
}
}
}
現在是第一個Fragment的XML和.java文件。
fragment_A.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center_horizontal"
>
<DatePicker
android:id="@+id/datePicker1"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</LinearLayout>
FragmentA.java
package com.example.android.fragments_proto.fragment;
import android.app.Activity;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.view.ViewGroup;
import android.widget.DatePicker;
import android.widget.Toast;
import com.example.android.fragments_proto.R;
public class FragmentA extends Fragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_A, container, false);
DatePicker datePicker = (DatePicker) view.findViewById(R.id.datePicker1);
datePicker.setCalendarViewShown(true);
datePicker.setSpinnersShown(false);
datePicker.setOnTouchListener(new OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
Activity activity = getActivity();
if (activity != null) {
Toast.makeText(activity, "You Touched ME!", Toast.LENGTH_SHORT).show();
}
return false;
}
});
return view;
}
}
現在的XML和.java文件包含挖掘時該按鈕的片斷將內容中的R .id.fragment_C
fragment_B。XML
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<LinearLayout
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="0dp"
android:layout_weight="0.1"
>
<ListView
android:id="@+id/listView1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
</ListView>
</LinearLayout>
<LinearLayout
android:layout_width="fill_parent"
android:orientation="horizontal"
android:gravity="center"
android:layout_height="wrap_content">
<Button
android:id="@+id/button"
android:text="@string/btn_fragment"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
/>
</LinearLayout>
</LinearLayout>
FragmentB.java
package com.example.android.fragments_proto.fragment;
import android.app.Activity;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentTransaction;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;
import com.example.android.fragments_proto.R;
public class FragmentB extends Fragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragmentB, container, false);
ListView listView = (ListView) view.findViewById(R.id.listView1);
Button button = (Button) view.findViewById(R.id.button);
String[] machines = new String[] { "MachineId-001", "MachineId-002", "MachineId-003", "MachineId-004", "MachineId-005", "MachineId-006", "MachineId-007", "MachineId-008"};
listView.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
listView.setAdapter(new ArrayAdapter<String>(getActivity(), android.R.layout.select_dialog_multichoice, machines));
final FrameLayout frameLayout = (FrameLayout) view.findViewById(R.id.fragment_C);
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Activity activity = getActivity();
if (activity != null) {
getFragmentManager().beginTransaction().replace(R.id.fragment_C, new FragmentC()).setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE).addToBackStack(null).commit();
frameLayout.setVisibility(View.VISIBLE);
}
}
});
return view;
}
}
的XML和.java文件針對的應該要添加的片段。
fragment_C.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<LinearLayout
android:layout_width="fill_parent"
android:orientation="horizontal"
android:gravity="center"
android:layout_height="wrap_content">
<Button
android:id="@+id/maximize_button"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Maximize Me!" />
</LinearLayout>
<TextView
android:id="@+id/text_view"
android:textIsSelectable="true"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#FF33FF"
/>
</LinearLayout>
FragmentC.java
package com.example.android.fragments_proto.fragment;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentTransaction;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.TextView;
import com.example.android.fragments_proto.R;
public class FragmentC extends Fragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_C, container, false);
TextView textView = (TextView) view.findViewById(R.id.text_view);
final Fragment fragmentA = getFragmentManager().findFragmentById(R.id.fragment_A);
final Fragment fragmentB = getFragmentManager().findFragmentById(R.id.fragment_B);
button.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
FragmentTransaction ft = getFragmentManager().beginTransaction();
if (fragmentA.isVisible() && fragmentB.isVisible()) {
ft.hide(fragmentA);
ft.hide(fragmentB);
fragmentA.getView().setVisibility(View.GONE);
fragmentB.getView().setVisibility(View.GONE);
button.setText("Minimize Me!");
ft.addToBackStack(null);
} else {
ft.show(fragmentA);
ft.show(fragmentB);
fragmentA.getView().setVisibility(View.VISIBLE);
fragmentB.getView().setVisibility(View.VISIBLE);
button.setText("Maximize Me!");
ft.addToBackStack(null);
}
ft.commit();
}
});
return view;
}
}
發現問題和解決方案由於Moesio
問題:
我的錯誤是,我試圖找到
最終的FrameLayout FrameLayout裏=(FrameLayout裏)view.findViewById(R.id一個視圖(FragmentB.java)。 fragment_C);
這行代碼返回null,所以當代碼達到它應該執行.setVisibility()然後應用程序。會返回一個nullPointerException。
FragmentC.java發生了同樣的情況(所以我的兩個問題是相關的)。視圖沒有被刪除,因爲我的findViewById爲null!
SOLUTION:
只要搜索你的瀏覽與getActivity .findViewById(R.id.your_view);
我粘貼代碼在本地的項目,我想我找到了「空」的原因。我編輯過可能會回答。參見下文。 – Moesio 2013-03-20 17:54:55