FragmentTabHost代码修改
- 关注几个魔数数字
- 修改为show/hide，不没次都进行加载
修改后的代码
package com.app.ch.fragmenttabhost.views.tabhost;
import android.content.Context;
import android.content.res.TypedArray;
import android.os.Bundle;
import android.os.Parcel;
import android.os.Parcelable;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.util.AttributeSet;
import android.view.View;
import android.widget.FrameLayout;
import android.widget.LinearLayout;
import android.widget.TabHost;
import android.widget.TabWidget;
import android.widget.TabHost.OnTabChangeListener;
import java.util.ArrayList;
public class FragmentTabHost extends TabHost implements OnTabChangeListener {
private final ArrayList<FragmentTabHost.TabInfo> mTabs = new ArrayList();
private FrameLayout mRealTabContent;
private Context mContext;
private FragmentManager mFragmentManager;
private int mContainerId;
private OnTabChangeListener mOnTabChangeListener;
private FragmentTabHost.TabInfo mLastTab;
private boolean mAttached;
public FragmentTabHost(Context context) {
super(context, (AttributeSet)null);
this.initFragmentTabHost(context, (AttributeSet)null);
}
public FragmentTabHost(Context context, AttributeSet attrs) {
super(context, attrs);
this.initFragmentTabHost(context, attrs);
}
private void initFragmentTabHost(Context context, AttributeSet attrs) {
TypedArray a = context.obtainStyledAttributes(attrs, new int[]{16842995}, 0, 0);
this.mContainerId = a.getResourceId(0, 0);
a.recycle();
super.setOnTabChangedListener(this);
}
private void ensureHierarchy(Context context) {
if (this.findViewById(android.R.id.tabs) == null) {
LinearLayout ll = new LinearLayout(context);
ll.setOrientation(LinearLayout.VERTICAL);
this.addView(ll, new LayoutParams(-1, -1));
TabWidget tw = new TabWidget(context);
tw.setId(android.R.id.tabs);
tw.setOrientation(LinearLayout.HORIZONTAL);
ll.addView(tw, new android.widget.LinearLayout.LayoutParams(-1, -2, 0.0F));
FrameLayout fl = new FrameLayout(context);
fl.setId(android.R.id.tabcontent);
ll.addView(fl, new android.widget.LinearLayout.LayoutParams(0, 0, 0.0F));
this.mRealTabContent = fl = new FrameLayout(context);
this.mRealTabContent.setId(this.mContainerId);
ll.addView(fl, new android.widget.LinearLayout.LayoutParams(-1, 0, 1.0F));
}
}
@Deprecated
public void setup() {
throw new IllegalStateException("Must call setup() that takes a Context and FragmentManager");
}
public void setup(Context context, FragmentManager manager) {
this.ensureHierarchy(context);
super.setup();
this.mContext = context;
this.mFragmentManager = manager;
this.ensureContent();
}
public void setup(Context context, FragmentManager manager, int containerId) {
this.ensureHierarchy(context);
super.setup();
this.mContext = context;
this.mFragmentManager = manager;
this.mContainerId = containerId;
this.ensureContent();
this.mRealTabContent.setId(containerId);
if (this.getId() == -1) {
this.setId(android.R.id.tabhost);
}
}
private void ensureContent() {
if (this.mRealTabContent == null) {
this.mRealTabContent = (FrameLayout)this.findViewById(this.mContainerId);
if (this.mRealTabContent == null) {
throw new IllegalStateException("No tab content FrameLayout found for id " + this.mContainerId);
}
}
}
public void setOnTabChangedListener(OnTabChangeListener l) {
this.mOnTabChangeListener = l;
}
public void addTab(@NonNull TabSpec tabSpec, @NonNull Class<?> clss, @Nullable Bundle args) {
tabSpec.setContent(new FragmentTabHost.DummyTabFactory(this.mContext));
String tag = tabSpec.getTag();
FragmentTabHost.TabInfo info = new FragmentTabHost.TabInfo(tag, clss, args);
if (this.mAttached) {
info.fragment = this.mFragmentManager.findFragmentByTag(tag);
if (info.fragment != null && !info.fragment.isDetached()) {
FragmentTransaction ft = this.mFragmentManager.beginTransaction();
ft.detach(info.fragment);
ft.commit();
}
}
this.mTabs.add(info);
this.addTab(tabSpec);
}
protected void onAttachedToWindow() {
super.onAttachedToWindow();
String currentTag = this.getCurrentTabTag();
FragmentTransaction ft = null;
int i = 0;
for(int count = this.mTabs.size(); i < count; ++i) {
FragmentTabHost.TabInfo tab = (FragmentTabHost.TabInfo)this.mTabs.get(i);
tab.fragment = this.mFragmentManager.findFragmentByTag(tab.tag);
if (tab.fragment != null && !tab.fragment.isDetached()) {
if (tab.tag.equals(currentTag)) {
this.mLastTab = tab;
} else {
if (ft == null) {
ft = this.mFragmentManager.beginTransaction();
}
ft.detach(tab.fragment);
}
}
}
this.mAttached = true;
ft = this.doTabChanged(currentTag, ft);
if (ft != null) {
ft.commit();
this.mFragmentManager.executePendingTransactions();
}
}
protected void onDetachedFromWindow() {
super.onDetachedFromWindow();
this.mAttached = false;
}
protected Parcelable onSaveInstanceState() {
Parcelable superState = super.onSaveInstanceState();
FragmentTabHost.SavedState ss = new FragmentTabHost.SavedState(superState);
ss.curTab = this.getCurrentTabTag();
return ss;
}
protected void onRestoreInstanceState(Parcelable state) {
if (!(state instanceof FragmentTabHost.SavedState)) {
super.onRestoreInstanceState(state);
} else {
FragmentTabHost.SavedState ss = (FragmentTabHost.SavedState)state;
super.onRestoreInstanceState(ss.getSuperState());
this.setCurrentTabByTag(ss.curTab);
}
}
public void onTabChanged(String tabId) {
if (this.mAttached) {
FragmentTransaction ft = this.doTabChanged(tabId, (FragmentTransaction)null);
if (ft != null) {
ft.commit();
}
}
if (this.mOnTabChangeListener != null) {
this.mOnTabChangeListener.onTabChanged(tabId);
}
}
@Nullable
private FragmentTransaction doTabChanged(@Nullable String tag, @Nullable FragmentTransaction ft) {
FragmentTabHost.TabInfo newTab = this.getTabInfoForTag(tag);
if (this.mLastTab != newTab) {
if (ft == null) {
ft = this.mFragmentManager.beginTransaction();
}
if (this.mLastTab != null && this.mLastTab.fragment != null) {
ft.hide(this.mLastTab.fragment);
}
if (newTab != null) {
if (newTab.fragment == null) {
newTab.fragment = Fragment.instantiate(this.mContext, newTab.clss.getName(), newTab.args);
ft.add(this.mContainerId, newTab.fragment, newTab.tag);
} else {
ft.show(newTab.fragment);
}
}
this.mLastTab = newTab;
}
return ft;
}
@Nullable
private FragmentTabHost.TabInfo getTabInfoForTag(String tabId) {
int i = 0;
for(int count = this.mTabs.size(); i < count; ++i) {
FragmentTabHost.TabInfo tab = (FragmentTabHost.TabInfo)this.mTabs.get(i);
if (tab.tag.equals(tabId)) {
return tab;
}
}
return null;
}
static class SavedState extends BaseSavedState {
String curTab;
public static final Creator<FragmentTabHost.SavedState> CREATOR = new Creator<FragmentTabHost.SavedState>() {
public FragmentTabHost.SavedState createFromParcel(Parcel in) {
return new FragmentTabHost.SavedState(in);
}
public FragmentTabHost.SavedState[] newArray(int size) {
return new FragmentTabHost.SavedState[size];
}
};
SavedState(Parcelable superState) {
super(superState);
}
SavedState(Parcel in) {
super(in);
this.curTab = in.readString();
}
public void writeToParcel(Parcel out, int flags) {
super.writeToParcel(out, flags);
out.writeString(this.curTab);
}
public String toString() {
return "FragmentTabHost.SavedState{" + Integer.toHexString(System.identityHashCode(this)) + " curTab=" + this.curTab + "}";
}
}
static class DummyTabFactory implements TabContentFactory {
private final Context mContext;
public DummyTabFactory(Context context) {
this.mContext = context;
}
public View createTabContent(String tag) {
View v = new View(this.mContext);
v.setMinimumWidth(0);
v.setMinimumHeight(0);
return v;
}
}
static final class TabInfo {
@NonNull
final String tag;
@NonNull
final Class<?> clss;
@Nullable
final Bundle args;
Fragment fragment;
TabInfo(@NonNull String _tag, @NonNull Class<?> _class, @Nullable Bundle _args) {
this.tag = _tag;
this.clss = _class;
this.args = _args;
}
}
}
