我创建了两个简单的计算器应用程序，它们运行良好。我想将这些代码放在一个新应用程序中（每个选项卡中的每个应用程序代码都有3个选项卡的滑动视图）。该应用程序的安装，打开和安装在三个标签中显示我想要的方式。我在每个标签中都有两个按钮。清除＆amp;计算。当我点击那些按钮（与ONCLICK事件连接到java代码进行计算）时，应用程序崩溃了。相同的代码在我之前创建的两个不同的应用程序中运行良好。 Android工作室也在我的java代码中没有显示错误。
// mainAcitvity.java代码
.tblBorder
{
border:1px solid #000; width:100%;
}
.center
{
align:center;
}
//标签0的代码（第一个标签）
package com.example.siv.mahalaxmipetroleums;
import android.support.design.widget.TabLayout;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
public class MainActivity extends AppCompatActivity {
/**
* The {@link android.support.v4.view.PagerAdapter} that will provide
* fragments for each of the sections. We use a
* {@link FragmentPagerAdapter} derivative, which will keep every
* loaded fragment in memory. If this becomes too memory intensive, it
* may be best to switch to a
* {@link android.support.v4.app.FragmentStatePagerAdapter}.
*/
private SectionsPagerAdapter mSectionsPagerAdapter;
/**
* The {@link ViewPager} that will host the section contents.
*/
private ViewPager mViewPager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
// Create the adapter that will return a fragment for each of the three
// primary sections of the activity.
mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());
// Set up the ViewPager with the sections adapter.
mViewPager = (ViewPager) findViewById(R.id.container);
mViewPager.setAdapter(mSectionsPagerAdapter);
TabLayout tabLayout = (TabLayout) findViewById(R.id.tabs);
tabLayout.setupWithViewPager(mViewPager);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
/**
* The fragment argument representing the section number for this
* fragment.
*/
private static final String ARG_SECTION_NUMBER = "section_number";
public PlaceholderFragment() {
}
/**
* Returns a new instance of this fragment for the given section
* number.
*/
public static PlaceholderFragment newInstance(int sectionNumber) {
PlaceholderFragment fragment = new PlaceholderFragment();
Bundle args = new Bundle();
args.putInt(ARG_SECTION_NUMBER, sectionNumber);
fragment.setArguments(args);
return fragment;
}
/* @Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_one, container, false);
TextView textView = (TextView) rootView.findViewById(R.id.section_label);
textView.setText(getString(R.string.section_format, getArguments().getInt(ARG_SECTION_NUMBER)));
return rootView;
}*/
}
/**
* A {@link FragmentPagerAdapter} that returns a fragment corresponding to
* one of the sections/tabs/pages.
*/
public class SectionsPagerAdapter extends FragmentPagerAdapter {
public SectionsPagerAdapter(FragmentManager fm) {
super(fm);
}
@Override
public Fragment getItem(int position) {
// getItem is called to instantiate the fragment for the given page.
// Return a PlaceholderFragment (defined as a static inner class below).
if (position == 0) {
return new DipToVol();
} else if (position == 1) {
return new VolToDip();
} else if (position ==2)
return new Temp_Density();
else
return PlaceholderFragment.newInstance(position + 1);
}
@Override
public int getCount() {
// Show 3 total pages.
return 3;
}
@Override
public CharSequence getPageTitle(int position) {
switch (position) {
case 0:
return "Dip-Vol";
case 1:
return "Vol-Dip";
case 2:
return "Temp-Dens";
}
return null;
}
}
}
//标签1的代码（第二个标签）
package com.example.siv.mahalaxmipetroleums;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.EditText;
import android.widget.TextView;
public class DipToVol extends Fragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_one, container, false);
return view;
}
public double calVol(short rad, short len, int height) {
double area;
area = (Math.PI * Math.pow(rad, 2) / 2) - Math.pow(rad, 2) * Math.asin(1 - (height / (double)rad)) - (rad - height) * Math.sqrt(height * (2 * rad - height));
return area*len*0.000001;
}
public void clickFun1 (View view)
{
int dipHSD = 0, dipMS = 0;
final short radHSD = 1219;
final short lenHSD = 6810;
final short radMS = 999;
final short lenMS = 6804;
double volHSD, volMS,volHSD1, volMS1;
EditText dipH = (EditText) view.findViewById(R.id.dipHSD1);
EditText dipM = (EditText) view.findViewById(R.id.dipMS1);
TextView volH = (TextView) view.findViewById(R.id.volHSD1);
TextView volM = (TextView) view.findViewById(R.id.volMS1);
try {
dipHSD = Integer.parseInt(dipH.getText().toString());
volHSD = calVol(radHSD, lenHSD, dipHSD);
volHSD1 = Math.round(volHSD);
volH.setText(volHSD1 + "");
}
catch (NumberFormatException e) {
volH.setText("");
}
try{ dipMS = Integer.parseInt(dipM.getText().toString());
volMS = calVol(radMS, lenMS, dipMS);
volMS1 = Math.round(volMS);
volM.setText(volMS1 + "");
}catch(NumberFormatException e){volM.setText("");}
}
public void clearFun1(View view){
EditText dipH = (EditText) view.findViewById(R.id.dipHSD1);
EditText dipM = (EditText) view.findViewById(R.id.dipMS1);
TextView volH = (TextView) view.findViewById(R.id.volHSD1);
TextView volM = (TextView) view.findViewById(R.id.volMS1);
volH.setText("");
volM.setText("");
dipH.setText("");
dipM.setText("");
}
}
//选项卡2的代码（第三个选项卡） - 这里没有太多代码。只是创建视图的代码。和你好世界的展示。
//简单日志cat引用我的代码中的错误
package com.example.siv.mahalaxmipetroleums;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.EditText;
import android.widget.TextView;
public class VolToDip extends Fragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_two, container, false);
return view;
}
private class Liquid_Height{
//final double radHSD = 121.9;
//final double lenHSD = 681.0;
//final double radMS = 99.9;
//final double lenMS = 680.4;
final double epsilon = 0.0001;
double dip,volume,radius,length;
// Inner Class
public Liquid_Height(double x, double y, double z){
radius = x;
length = y;
volume = z;
double ratio,guess,dip1;
ratio = this.volume*1000/(radius*radius*length);
guess = 2*ratio/Math.PI;
dip1 = height(guess,ratio,epsilon);
dip = dip1*radius;
}
public double fun1(double x,double y){
//here x is our guess or result which we try to improve upon, and y is ratio = V/R*R*L
return Math.acos(1-x) + Math.sqrt(x*(2-x))*(x-1) - y ;
}
public double fun2(double x){
//here x is our guess or or result which we try to improve upon.
return 2*Math.sqrt(x*(2-x));
}
public boolean isGoodEnough(double x,double y,double e){
//here x is our guess or result which we try to improve upon, and y is ratio = V/R*R*L and e is epsilon
return Math.abs((Math.acos (1-x) + Math.sqrt(x*(2-x))*(x-1) - y)/y)> e;
}
public double height(double a,double b,double c){
//here a is our guess or result which we try to improve upon, and b is ratio = V/R*R*L and c is epsilon
while (isGoodEnough(a,b,c)){
a = a - fun1(a,b)/fun2(a);
}
return a;
}
public double getDip(){return dip;}
} //Inner class ends here
public void clickFun2 (View view)
{
EditText volH = (EditText) view.findViewById(R.id.volHSD2);
EditText volM = (EditText) view.findViewById(R.id.volMS2);
TextView dipH = (TextView) view.findViewById(R.id.dipHSD2);
TextView dipM = (TextView) view.findViewById(R.id.dipMS2);
double volHSD = 0, volMS = 0;
final double radHSD = 121.9;
final double lenHSD = 681.0;
final double radMS = 99.9;
final double lenMS = 680.4;
double dipHSD, dipMS;
try {
volHSD = Double.parseDouble(volH.getText().toString());
Liquid_Height HSD = new Liquid_Height(radHSD,lenHSD,volHSD);
dipHSD = Math.round(HSD.getDip()*10.0)/10.0;
dipH.setText(dipHSD + "");
}
catch (NumberFormatException e) {
dipH.setText("");
}
try{ volMS = Double.parseDouble(volM.getText().toString());
Liquid_Height MS = new Liquid_Height(radMS,lenMS,volMS);
dipMS = Math.round(MS.getDip()*10.0)/10.0;
dipM.setText(dipMS + "");
}
catch(NumberFormatException e){
dipM.setText("");
}
}
public void clearFun2(View view){
EditText volH = (EditText) view.findViewById(R.id.volHSD2);
EditText volM = (EditText) view.findViewById(R.id.volMS2);
TextView dipH = (TextView) view.findViewById(R.id.dipHSD2);
TextView dipM = (TextView) view.findViewById(R.id.dipMS2);
volH.setText("");
volM.setText("");
dipH.setText("");
dipM.setText("");
}
}
任何人都可以找到那个错误吗???
答案 0 :(得分：2)
java.lang.IllegalStateException: Could not find method clickFun1(View) in a parent or ancestor Context for android:onClick attribute defined on view class android.support.v7.widget.AppCompatButton with id 'calcBtn'
您的布局具有android:onClick属性，指的是clickFun1方法。您的活动上没有该名称的方法。 是一个在你的某个片段上使用该名称的方法，但标准的android:onClick逻辑将找不到那个。
处理此问题的选项包括：
删除android:onClick属性，而不是在片段中的此按钮上注册OnClickListener
摆脱片段，将业务逻辑（包括此clickFun1()方法）移入活动
使用the data binding library将android:onClick属性与您的片段联系起来
如果您不熟悉Android开发，我建议您使用第一个选项。