java.lang.RuntimeException：无法启动查看器。 API GraphStream-Android

Question

你好，我是 android 开发新手，正在为大学工作，创建一个可以创建图形（图论）和执行算法的应用程序，我选择使用 graphstream，因为它是一个图形库，但我遇到了一些问题，我无法将节点放在视图上布局在一个片段中，因为我正在使用两个活动，一个用于绘制图形，另一个用于选择算法。（这只是一个测试，看看图形是否出现在屏幕上，我会尝试实现按钮，以便用户创建自己的图形）。

这是我的 java 代码：

package com.projeto.gabriel.athenatgfinal;

import android.content.Intent;
import android.graphics.Color;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.design.widget.BottomNavigationView;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Toast;

import org.graphstream.graph.Graph;
import org.graphstream.graph.implementations.SingleGraph;
import org.graphstream.ui.android_viewer.DefaultView;

public class FragmentGrafo extends Fragment {

@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
   final View view = inflater.inflate(R.layout.grafo_fragment, container, false);

   BottomNavigationView bottomNavigationView = view.findViewById(R.id.bottomNavView);
   bottomNavigationView.setOnNavigationItemSelectedListener(selectedListener);

   return view;
}

private BottomNavigationView.OnNavigationItemSelectedListener selectedListener
        = new BottomNavigationView.OnNavigationItemSelectedListener() {
    @Override
    public boolean onNavigationItemSelected(@NonNull MenuItem item) {
        switch (item.getItemId()) {
            case R.id.action_add_node:
                Toast.makeText(getActivity(), "Clicou em add nó", Toast.LENGTH_SHORT).show();
                return true;

            case R.id.action_add_aresta:
                Toast.makeText(getActivity(), "aresta aqui", Toast.LENGTH_SHORT).show();
                return true;

            case R.id.action_remover:
                Toast.makeText(getActivity(), "remover", Toast.LENGTH_SHORT).show();
                return true;
        }
        return false;
    }
};

@Override
public void onCreate(@Nullable Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    System.setProperty("org.graphstream.ui.renderer","org.graphstream.ui.j2dviewer.J2DGraphRenderer");
   Graph graph = new SingleGraph("tutorial 1");

    graph.addNode("A" );
    graph.addNode("B" );
    graph.addNode("C" );
    graph.addEdge("AB", "A", "B");
    graph.addEdge("BC", "B", "C");
    graph.addEdge("CA", "C", "A");

    graph.display();
 }
}

这是我的布局：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:app="http://schemas.android.com/apk/res-auto">

<org.graphstream.ui.android_viewer.util.DefaultFragment
    android:id="@+id/fragment_tag"
    android:layout_width="wrap_content"
    android:layout_height="match_parent"
    android:layout_above="@+id/bottomNavView"
    android:layout_alignParentStart="true"
    android:layout_alignParentTop="true"
    android:layout_alignParentEnd="true"
    android:layout_marginStart="0dp"
    android:layout_marginTop="369dp"
    android:layout_marginEnd="0dp"
    android:layout_marginBottom="287dp" />

<include layout="@layout/bottom_nav_view"
    android:id="@+id/bottomNavView"/>

</RelativeLayout>

这是我的 bottomNavView，我正在尝试放置一个事件来单击并绘制节点和边并删除它们：

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.BottomNavigationView
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_alignParentBottom="true"
    android:layout_alignParentStart="true"
    app:itemBackground="@color/colorPrimary"
    app:itemIconTint="@color/nav_item_color"
    app:itemTextColor="@color/nav_item_color"
    app:menu="@menu/menu_grafo">

</android.support.design.widget.BottomNavigationView>

这是我的错误：

--------- beginning of crash
E/AndroidRuntime: FATAL EXCEPTION: main Process: com.projeto.gabriel.athenatgf, PID: 6000 java.lang.RuntimeException: Cannot launch viewer. at org.graphstream.graph.implementations.AbstractGraph.display(AbstractGraph.java:212) at org.graphstream.graph.implementations.AbstractGraph.display(AbstractGraph.java:204) at com.projeto.gabriel.athenatgfinal.FragmentGrafo.onCreate(FragmentGrafo.java:67) at android.support.v4.app.Fragment.performCreate(Fragment.java:2414) at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1418) at android.support.v4.app.FragmentTransition.addToFirstInLastOut(FragmentTransition.java:1195) at android.support.v4.app.FragmentTransition.calculateFragments(FragmentTransition.java:1078) at android.support.v4.app.FragmentTransition.startTransitions(FragmentTransition.java:117) at android.support.v4.app.FragmentManagerImpl.executeOpsTogether(FragmentManager.java:2408) at android.support.v4.app.FragmentManagerImpl.removeRedundantOperationsAndExecute(FragmentManager.java:2366) at android.support.v4.app.FragmentManagerImpl.execSingleAction(FragmentManager.java:2243) at android.support.v4.app.BackStackRecord.commitNowAllowingStateLoss(BackStackRecord.java:654) at android.support.v4.app.FragmentPagerAdapter.finishUpdate(FragmentPagerAdapter.java:146) at android.support.v4.view.ViewPager.populate(ViewPager.java:1244) at android.support.v4.view.ViewPager.populate(ViewPager.java:1092) at android.support.v4.view.ViewPager.onMeasure(ViewPager.java:1622) at android.view.View.measure(View.java:19857) at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6083) at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1464) at android.widget.LinearLayout.measureVertical(LinearLayout.java:758) at android.widget.LinearLayout.onMeasure(LinearLayout.java:640) at android.view.View.measure(View.java:19857) at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6083) at android.widget.FrameLayout.onMeasure(FrameLayout.java:185) at android.support.v7.widget.ContentFrameLayout.onMeasure(ContentFrameLayout.java:143) at android.view.View.measure(View.java:19857) at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6083) at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1464) at android.widget.LinearLayout.measureVertical(LinearLayout.java:758) at android.widget.LinearLayout.onMeasure(LinearLayout.java:640) at android.view.View.measure(View.java:19857) at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6083) at android.widget.FrameLayout.onMeasure(FrameLayout.java:185) at android.view.View.measure(View.java:19857) at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6083) at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1464) at android.widget.LinearLayout.measureVertical(LinearLayout.java:758) at android.widget.LinearLayout.onMeasure(LinearLayout.java:640) at android.view.View.measure(View.java:19857) at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6083) at android.widget.FrameLayout.onMeasure(FrameLayout.java:185) at com.android.internal.policy.DecorView.onMeasure(DecorView.java:690) at android.view.View.measure(View.java:19857) at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:2275) at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1366) at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1619) at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1254) at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6338) at android.view.Choreographer$CallbackRecord.run(Choreographer.java:874) at android.view.Choreographer.doCallbacks(Choreographer.java:686) at android.view.Choreographer.doFrame(Choreographer.java:621) at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:860) at android.os.Handler.handleCallback(Handler.java:751) at android.os.Handler.dispatchMessage(Handler.java:95) at android.os.Looper.loop(Looper.java:154) at android.app.ActivityThread.main(ActivityThread.java:6169) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:891) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:781) Caused by: org.graphstream.util.MissingDisplayException: No UI package detected! Please use System.setProperty("org.graphstream.ui") for the selected package. at org.graphstream.util.Display.getDefault(Display.java:55) at org.graphstream.graph.implementations.AbstractGraph.display(AbstractGraph.java:209) ... 58 more Application terminated.

我的问题是如何纠正这个问题？这是最好的方法吗？感谢阅读，请帮助我。

Answer 1

您不能使用 Graphstream 1.3 和常规的 display() 方法。如果你想开发一个android应用程序，你必须使用Graphstream 2.0 with the Android UI

您可以找到一些示例 here 来帮助您。

java.lang.RuntimeException：无法启动查看器。 API GraphStream-Android

java.lang.RuntimeException: Cannot launch viewer. API GraphStream-Android

java

android

graph

graphstream