Question

你好，我是android开发的新手，正在为大学做一个工作，创建一个可以创建（图论）图并执行算法的应用程序，我选择使用graphstream，因为它是一个图库，但是我有一些问题，我无法将节点放在视图上布局是一个片段，因为我正在使用两次激活来绘制图形，而另一次选择算法。（这只是一项测试，看图表是否出现在屏幕上，我将尝试实现按钮，以便用户创建自己的图表）。

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以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 / Android运行时：致命异常：主要流程：com.projeto.gabriel.athenatgf，PID：6000 java.lang.RuntimeException：无法启动查看器。在org.graphstream.graph.implementations.AbstractGraph.display（AbstractGraph.java:212）在org.graphstream.graph.implementations.AbstractGraph.display（AbstractGraph.java:204）在com.projeto.gabriel.athenatgfinal.FragmentGrafo.onCreate（FragmentGrafo.java:67）在android.support.v4.app.Fragment.performCreate（Fragment.java:2414）在android.support.v4.app.FragmentManagerImpl.moveToState（FragmentManager.java:1418）在android.support.v4.app.FragmentTransition.addToFirstInLastOut（FragmentTransition.java:1195）在android.support.v4.app.FragmentTransition.calculateFragments（FragmentTransition.java:1078）在android.support.v4.app.FragmentTransition.startTransitions（FragmentTransition.java:117）在android.support.v4.app.FragmentManagerImpl.executeOpsTogether（FragmentManager.java:2408）在android.support.v4.app.FragmentManagerImpl.removeRedundantOperationsAndExecute（FragmentManager.java:2366）在android.support.v4.app.FragmentManagerImpl.execSingleAction（FragmentManager.java:2243）在android.support.v4.app.BackStackRecord.commitNowAllowingStateLoss（BackStackRecord.java:654）在android.support.v4.app.FragmentPagerAdapter.finishUpdate（FragmentPagerAdapter.java:146）在android.support.v4.view.ViewPager.populate（ViewPager.java:1244）在android.support.v4.view.ViewPager.populate（ViewPager.java:1092）在android.support.v4.view.ViewPager.onMeasure（ViewPager.java:1622）在android.view.View.measure（View.java:19857）在android.view.ViewGroup.measureChildWithMargins（ViewGroup.java:6083）在android.widget.LinearLayout.measureChildBeforeLayout（LinearLayout.java:1464）在android.widget.LinearLayout.measureVertical（LinearLayout.java:758）在android.widget.LinearLayout.onMeasure（LinearLayout.java:640）在android.view.View.measure（View.java:19857）在android.view.ViewGroup.measureChildWithMargins（ViewGroup.java:6083）在android.widget.FrameLayout.onMeasure（FrameLayout.java:185）在android.support.v7.widget.ContentFrameLayout.onMeasure（ContentFrameLayout.java:143）在android.view.View.measure（View.java:19857）在android.view.ViewGroup.measureChildWithMargins（ViewGroup.java:6083）在android.widget.LinearLayout.measureChildBeforeLayout（LinearLayout.java:1464）在android.widget.LinearLayout.measureVertical（LinearLayout.java:758）在android.widget.LinearLayout.onMeasure（LinearLayout.java:640）在android.view.View.measure（View.java:19857）在android.view.ViewGroup.measureChildWithMargins（ViewGroup.java:6083）在android.widget.FrameLayout.onMeasure（FrameLayout.java:185）在android.view.View.measure（View.java:19857）在android.view.ViewGroup.measureChildWithMargins（ViewGroup.java:6083）在android.widget.LinearLayout.measureChildBeforeLayout（LinearLayout.java:1464）在android.widget.LinearLayout.measureVertical（LinearLayout.java:758）在android.widget.LinearLayout.onMeasure（LinearLayout.java:640）在android.view.View.measure（View.java:19857）在android.view.ViewGroup.measureChildWithMargins（ViewGroup.java:6083）在android.widget.FrameLayout.onMeasure（FrameLayout.java:185）在com.android.internal.policy.DecorView.onMeasure（DecorView.java:690）在android.view.View.measure（View.java:19857）在android.view.ViewRootImpl.performMeasure（ViewRootImpl.java:2275）在android.view.ViewRootImpl.measureHierarchy（ViewRootImpl.java:1366）在android.view.ViewRootImpl.performTraversals（ViewRootImpl.java:1619）在android.view.ViewRootImpl.doTraversal（ViewRootImpl.java:1254）在android.view.ViewRootImpl $ TraversalRunnable.run（ViewRootImpl.java:6338）在android.view.Choreographer $ CallbackRecord.run（Choreographer.java:874）在android.view.Choreographer.doCallbacks（Choreographer.java:686）在android.view.Choreographer.doFrame（Choreographer.java:621）在android.view.Choreographer $ FrameDisplayEventReceiver.run（Choreographer.java:860）在android.os.Handler.handleCallback（Handler.java:751）在android.os.Handler.dispatchMessage（Handler.java:95）在android.os.Looper.loop（Looper.java:154）在android.app.ActivityThread.main（ActivityThread.java:6169）在java.lang.reflect.Method.invoke（本机方法）在com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run（ZygoteInit.java:891）在com.android.internal.os.ZygoteInit.main（ZygoteInit.java:781）原因：org.graphstream.util.MissingDisplayException：未检测到UI包！请对所选包使用System.setProperty（“ org.graphstream.ui”）。在org.graphstream.util.Display.getDefault（Display.java:55）在org.graphstream.graph.implementations.AbstractGraph.display（AbstractGraph.java:209） ...更多58 应用已终止。

我的问题是如何纠正此问题？，这是做到这一点的最佳方法？感谢您的阅读，请帮助我。

Answer 1

您不能使用Graphstream 1.3和常规的display（）方法。如果要开发Android应用程序，则必须将Graphstream 2.0与Android UI

一起使用

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

1 个答案: