我想将Seekbar实现为Fragment。我可以将其实现为任何活动都没有问题，但是对于我的片段来说，它是行不通的。它应该显示0-360之间的数字。
我试图在碎片中实现seekbar侦听器，但是我无法使用findviewbyid。
第一部分是我的片段，第二部分是主要活动。
package com.example.holdingpattern;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.support.annotation.Nullable;
public class holdingfragment extends Fragment {
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment_holding, null);
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package com.example.holdingpattern;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.design.widget.BottomNavigationView;
import android.support.v4.app.Fragment;
import android.support.v7.app.AppCompatActivity;
import android.view.MenuItem;
import android.widget.SeekBar;
import android.widget.TextView;
public class MainActivity extends AppCompatActivity implements BottomNavigationView.OnNavigationItemSelectedListener {
TextView textView;
SeekBar seekBar;
int min = 0, max = 360, current = 360;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
BottomNavigationView navView = findViewById(R.id.nav_view);
navView.setOnNavigationItemSelectedListener(this);
loadFragment(new holdingfragment());
textView = findViewById(R.id.textView4);
seekBar = findViewById(R.id.seekBar2);
seekBar.setMax(max - min);
seekBar.setProgress(current - min);
textView.setText("" + current);
seekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
@Override
public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
current = progress + min;
textView.setText("" + current);
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
}
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
}
});
}
private boolean loadFragment (Fragment fragment){
if(fragment !=null){
getSupportFragmentManager()
.beginTransaction()
.replace(R.id.fragment_container, fragment)
.commit();
return true;
}
return false;
}
@Override
public boolean onNavigationItemSelected(@NonNull MenuItem menuItem) {
Fragment fragment = null;
switch (menuItem.getItemId()){
case R.id.navigation_holding:
fragment = new holdingfragment();
break;
case R.id.navigation_wind:
fragment = new windfragment();
break;
case R.id.navigation_answer:
fragment = new answerfragment();
break;
}
return loadFragment(fragment);
}
}