我已经使用 Viewpager 创建了可滑动的选项卡，但由于某种原因，我无法在我的 xml 文件中显示正确的选项卡名称。继承人的类：
dashboard.xml（标签显示的 xml）：
<TabHost
android:id="@android:id/tabhost"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<TabWidget
android:id="@android:id/tabs"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
</TabWidget>
<FrameLayout
android:id="@android:id/tabcontent"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<FrameLayout
android:id="@+id/tab1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:visibility="gone" />
<FrameLayout
android:id="@+id/tab2"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:visibility="gone" />
<FrameLayout
android:id="@+id/tab3"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:visibility="gone" />
<FrameLayout
android:id="@+id/tab4"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:visibility="gone" />
<FrameLayout
android:id="@+id/tab5"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:visibility="gone" />
</FrameLayout>
<android.support.v4.view.ViewPager
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/pager"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
</LinearLayout>
</TabHost>
TabsViewPagerFragmentActivity.java：
package com.example.loginandregistration;
IMPORTS
public class TabsViewPagerFragmentActivity extends Activity implements OnTabChangeListener, OnPageChangeListener{
private TabHost host;
private ViewPager pager;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.dashboard);
host = (TabHost)findViewById(android.R.id.tabhost);
pager = (ViewPager) findViewById(R.id.pager);
host.setup();
TabSpec spec = host.newTabSpec("Create Pic");
spec.setContent(R.id.tab1);
spec.setIndicator("Create Pic");
host.addTab(spec);
spec = host.newTabSpec("Send Pic");
spec.setContent(R.id.tab2);
spec.setIndicator("Send Pic");
host.addTab(spec);
spec = host.newTabSpec("Create Folder");
spec.setContent(R.id.tab3);
spec.setIndicator("Create Folder");
host.addTab(spec);
spec = host.newTabSpec("Feedback");
spec.setContent(R.id.tab4);
spec.setIndicator("Feedback");
host.addTab(spec);
spec = host.newTabSpec("Logout");
spec.setContent(R.id.tab5);
spec.setIndicator("Log Out");
host.addTab(spec);
pager.setAdapter(new MyPageAdapter(this));
pager.setOnPageChangeListener(this);
host.setOnTabChangedListener(this);
}
@Override
public void onTabChanged(String tabId){
int pageNumber = 0;
if(tabId.equals("tab1")){
pageNumber = 0;
} else if(tabId.equals("tab2")){
pageNumber = 1;
} else{
pageNumber = 2;
}
pager.setCurrentItem(pageNumber);
}
@Override
public void onPageSelected(int pageNumber) {
host.setCurrentTab(pageNumber);
}
@Override
public void onPageScrollStateChanged(int arg0) {
// TODO Auto-generated method stub
}
@Override
public void onPageScrolled(int arg0, float arg1, int arg2) {
// TODO Auto-generated method stub
}
}
补充：
当我在模拟器上运行我的应用程序时，tabhost 不会显示在我的仪表板中。正如你在这里看到的
补充：
这是我的页面适配器：
package com.example.loginandregistration;
IMPORTS
public class MyPageAdapter extends PagerAdapter {
private Context ctx;
public MyPageAdapter(Context ctx){
this.ctx = ctx;
}
@Override
public Object instantiateItem(ViewGroup container, int position) {
TextView tView = new TextView(ctx);
position++;
tView.setText("Page number: " + position);
tView.setTextColor(Color.RED);
tView.setTextSize(20);
container.addView(tView);
return tView;
}
@Override
public int getCount() {
return 3;
}
@Override
public boolean isViewFromObject(View view, Object object) {
return (view == object);
}
}
另外，我刚刚注意到这一点，但是，我将如何更改编码以便我的选项卡转到其他类？
添加：我现在收到以下七个错误：
Description Resource Path Location Type
FragmentTab3 cannot be resolved to a type MyPageAdapter.java /LoginAndRegistration/src/com/example/loginandregistration line 33 Java Problem
FragmentTab1 cannot be resolved to a type MyPageAdapter.java /LoginAndRegistration/src/com/example/loginandregistration line 23 Java Problem
FragmentTab3 cannot be resolved to a type MyPageAdapter.java /LoginAndRegistration/src/com/example/loginandregistration line 33 Java Problem
FragmentTab1 cannot be resolved to a type MyPageAdapter.java /LoginAndRegistration/src/com/example/loginandregistration line 23 Java Problem
FragmentTab2 cannot be resolved to a type MyPageAdapter.java /LoginAndRegistration/src/com/example/loginandregistration line 28 Java Problem
FragmentTab2 cannot be resolved to a type MyPageAdapter.java /LoginAndRegistration/src/com/example/loginandregistration line 28 Java Problem
fm cannot be resolved to a variable TabsViewPagerFragmentActivity.java /LoginAndRegistration/src/com/example/loginandregistration line 47 Java Problem
这是我更新的 MyPageAdapter：
package com.example.loginandregistration;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
public class MyPageAdapter extends FragmentPagerAdapter {
// Declare the number of ViewPager pages
final int PAGE_COUNT = 3;
public MyPageAdapter(FragmentManager fm) {
super(fm);
}
@Override
public Fragment getItem(int arg0) {
switch (arg0) {
// Open FragmentTab1.java
case 0:
FragmentTab1 fragmenttab1 = new FragmentTab1();
return fragmenttab1;
// Open FragmentTab2.java
case 1:
FragmentTab2 fragmenttab2 = new FragmentTab2();
return fragmenttab2;
// Open FragmentTab3.java
case 2:
FragmentTab3 fragmenttab3 = new FragmentTab3();
return fragmenttab3;
}
return null;
}
@Override
public int getCount() {
// TODO Auto-generated method stub
return PAGE_COUNT;
}
}
这是我更新的 TabsViewFragmentActivity：
package com.example.loginandregistration;
import android.app.ActionBar;
import android.app.ActionBar.Tab;
import android.app.FragmentManager;
import android.app.FragmentTransaction;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.support.v4.view.ViewPager;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.content.LocalBroadcastManager;
import com.example.loginandregistration.MyPageAdapter;
public class TabsViewPagerFragmentActivity extends FragmentActivity {
// Declare Variables
ActionBar mActionBar;
ViewPager mPager;
Tab tab;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Get the view from dashboard.xml
setContentView(R.layout.dashboard);
// Activate Navigation Mode Tabs
mActionBar = getActionBar();
mActionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
// Locate ViewPager in activity_main.xml
mPager = (ViewPager) findViewById(R.id.pager);
// Capture ViewPager page swipes
ViewPager.SimpleOnPageChangeListener ViewPagerListener = new ViewPager.SimpleOnPageChangeListener() {
@Override
public void onPageSelected(int position) {
super.onPageSelected(position);
// Find the ViewPager Position
mActionBar.setSelectedNavigationItem(position);
}
};
mPager.setOnPageChangeListener(ViewPagerListener);
// Locate the adapter class called ViewPagerAdapter.java
MyPageAdapter viewpageradapter = new MyPageAdapter(fm);
// Set the View Pager Adapter into ViewPager
mPager.setAdapter(viewpageradapter);
// Capture tab button clicks
ActionBar.TabListener tabListener = new ActionBar.TabListener() {
@Override
public void onTabSelected(Tab tab, FragmentTransaction ft) {
// Pass the position on tab click to ViewPager
mPager.setCurrentItem(tab.getPosition());
}
@Override
public void onTabUnselected(Tab tab, FragmentTransaction ft) {
// TODO Auto-generated method stub
}
@Override
public void onTabReselected(Tab tab, FragmentTransaction ft) {
// TODO Auto-generated method stub
}
};
// Create first Tab
tab = mActionBar.newTab().setText("Tab1").setTabListener(tabListener);
mActionBar.addTab(tab);
// Create second Tab
tab = mActionBar.newTab().setText("Tab2").setTabListener(tabListener);
mActionBar.addTab(tab);
// Create third Tab
tab = mActionBar.newTab().setText("Tab3").setTabListener(tabListener);
mActionBar.addTab(tab);
}
}
我试图将我的 FragmentTabs 更改为我正在使用的类（例如 CreatePic.java：
package com.example.loginandregistration;
IMPORTS
public class CreatePic extends View {
//drawing path
private Path drawPath;
//drawing and canvas paint
private Paint drawPaint, canvasPaint;
//initial color
private int paintColor = 0xFF660000, paintAlpha = 255;
//canvas
private Canvas drawCanvas;
//canvas bitmap
private Bitmap canvasBitmap;
//brush sizes
private float brushSize, lastBrushSize;
//erase flag
private boolean erase=false;
public CreatePic(Context context, AttributeSet attrs){
super(context, attrs);
setupDrawing();
}
//setup drawing
private void setupDrawing(){
//prepare for drawing and setup paint stroke properties
brushSize = getResources().getInteger(R.integer.medium_size);
lastBrushSize = brushSize;
drawPath = new Path();
drawPaint = new Paint();
drawPaint.setColor(paintColor);
drawPaint.setAntiAlias(true);
drawPaint.setStrokeWidth(brushSize);
drawPaint.setStyle(Paint.Style.STROKE);
drawPaint.setStrokeJoin(Paint.Join.ROUND);
drawPaint.setStrokeCap(Paint.Cap.ROUND);
canvasPaint = new Paint(Paint.DITHER_FLAG);
}
//size assigned to view
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
canvasBitmap = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
drawCanvas = new Canvas(canvasBitmap);
}
//draw the view - will be called after touch event
@Override
protected void onDraw(Canvas canvas) {
canvas.drawBitmap(canvasBitmap, 0, 0, canvasPaint);
canvas.drawPath(drawPath, drawPaint);
}
//register user touches as drawing action
@Override
public boolean onTouchEvent(MotionEvent event) {
float touchX = event.getX();
float touchY = event.getY();
//respond to down, move and up events
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
drawPath.moveTo(touchX, touchY);
break;
case MotionEvent.ACTION_MOVE:
drawPath.lineTo(touchX, touchY);
break;
case MotionEvent.ACTION_UP:
drawPath.lineTo(touchX, touchY);
drawCanvas.drawPath(drawPath, drawPaint);
drawPath.reset();
break;
default:
return false;
}
//redraw
invalidate();
return true;
}
//update color
public void setColor(String newColor){
invalidate();
//check whether color value or pattern name
if(newColor.startsWith("#")){
paintColor = Color.parseColor(newColor);
drawPaint.setColor(paintColor);
drawPaint.setShader(null);
}
else{
//pattern
int patternID = getResources().getIdentifier(
newColor, "drawable", "com.example.loginandregistration");
//decode
Bitmap patternBMP = BitmapFactory.decodeResource(getResources(), patternID);
//create shader
BitmapShader patternBMPshader = new BitmapShader(patternBMP,
Shader.TileMode.REPEAT, Shader.TileMode.REPEAT);
//color and shader
drawPaint.setColor(0xFFFFFFFF);
drawPaint.setShader(patternBMPshader);
}
}
//set brush size
public void setBrushSize(float newSize){
float pixelAmount = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP,
newSize, getResources().getDisplayMetrics());
brushSize=pixelAmount;
drawPaint.setStrokeWidth(brushSize);
}
//get and set last brush size
public void setLastBrushSize(float lastSize){
lastBrushSize=lastSize;
}
public float getLastBrushSize(){
return lastBrushSize;
}
//set erase true or false
public void setErase(boolean isErase){
erase=isErase;
if(erase) drawPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.CLEAR));
else drawPaint.setXfermode(null);
}
//start new drawing
public void startNew(){
drawCanvas.drawColor(0, PorterDuff.Mode.CLEAR);
invalidate();
}
//return current alpha
public int getPaintAlpha(){
return Math.round((float)paintAlpha/255*100);
}
//set alpha
public void setPaintAlpha(int newAlpha){
paintAlpha=Math.round((float)newAlpha/100*255);
drawPaint.setColor(paintColor);
drawPaint.setAlpha(paintAlpha);
}
}
但我得到了一个错误循环。) 我完全不明白如何修复“fm”错误。有人告诉我，在我的 CreatePic 和其他类中他们必须扩展 Fragment，这是真的吗？如果是这样，有没有更简单的方法来做到这一点，这样我就不必重写所有的编码来适应它？