GraphView
Android GraphView is used to display data in graph structures.
Overview
The library is designed to support different graph layouts and currently works with small graphs only.
This project is currently experimental and the API subject to breaking changes without notice.
Download
dependencies {
implementation 'de.blox:graphview:0.6.1'
}
Layouts
Tree
Uses Walker's algorithm with Buchheim's runtime improvements (BuchheimWalkerAlgorithm
class). Supports different orientations. All you have to do is using the BuchheimWalkerConfiguration.Builder.setOrientation(int)
with either ORIENTATION_LEFT_RIGHT
, ORIENTATION_RIGHT_LEFT
, ORIENTATION_TOP_BOTTOM
and
ORIENTATION_BOTTOM_TOP
(default). Furthermore parameters like sibling-, level-, subtree separation can be set.
Directed graph
Directed graph drawing by simulating attraction/repulsion forces. For this the algorithm by Fruchterman and Reingold (FruchtermanReingoldAlgorithm
class) was implemented.
Layered graph
Algorithm from Sugiyama et al. for drawing multilayer graphs, taking advantage of the hierarchical structure of the graph (SugiyamaAlgorithm
class). You can also set the parameters for node and level separation using the SugiyamaConfiguration.Builder
.
Usage
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<de.blox.graphview.GraphView
android:id="@+id/graph"
android:layout_width="match_parent"
android:layout_height="match_parent">
</de.blox.graphview.GraphView>
</LinearLayout>
You can make the node Layout how you like. Just define a layout file, e.g. node.xml
...
<android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:card_view="http://schemas.android.com/apk/res-auto"
android:id="@+id/card_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_margin="5dp"
card_view:cardBackgroundColor="@android:color/holo_blue_dark"
card_view:cardElevation="16dp"
card_view:contentPadding="10dp">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TextView
android:id="@+id/textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="@android:color/white"
android:textStyle="bold"/>
</LinearLayout>
</android.support.v7.widget.CardView>
... and use it with the adapter
public class MainActivity extends AppCompatActivity {
private int nodeCount = 1;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
GraphView graphView = findViewById(R.id.graph);
// example tree
final Graph graph = new Graph();
final Node node1 = new Node(getNodeText());
final Node node2 = new Node(getNodeText());
final Node node3 = new Node(getNodeText());
graph.addEdge(node1, node2);
graph.addEdge(node1, node3);
// you can set the graph via the constructor or use the adapter.setGraph(Graph) method
final BaseGraphAdapter<ViewHolder> adapter = new BaseGraphAdapter<ViewHolder>(graph) {
@NonNull
@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
final View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.node, parent, false);
return new SimpleViewHolder(view);
}
@Override
public void onBindViewHolder(ViewHolder viewHolder, Object data, int position) {
((SimpleViewHolder)viewHolder).textView.setText(data.toString());
}
};
graphView.setAdapter(adapter);
// set the algorithm here
final BuchheimWalkerConfiguration configuration = new BuchheimWalkerConfiguration.Builder()
.setSiblingSeparation(100)
.setLevelSeparation(300)
.setSubtreeSeparation(300)
.setOrientation(BuchheimWalkerConfiguration.ORIENTATION_TOP_BOTTOM)
.build();
adapter.setAlgorithm(new BuchheimWalkerAlgorithm(configuration));
}
private String getNodeText() {
return "Node " + nodeCount++;
}
}
Your ViewHolder class should extend from ViewHolder:
class SimpleViewHolder extends ViewHolder {
TextView textView;
SimpleViewHolder(View itemView) {
super(itemView);
textView = itemView.findViewById(R.id.textView);
}
}
Customization
To use the custom attributes you have to add the namespace first: xmlns:app="http://schemas.android.com/apk/res-auto"
Attribute | Format | Example | Explanation |
---|---|---|---|
lineThickness | Dimension | 10dp | Set how thick the connection lines should be |
lineColor | Color | "@android:color/holo_red_dark" | Set the color of the connection lines |
useMaxSize | Boolean | true | Use the same size for each node |
Each of the attributes has a corresponding setter in the GraphView class, if you want to use it programmatically.
GraphView internally uses ZoomLayout for its zoom feature. To change the zoom values just use the different attributes described in the ZoomLayout project site.
Examples
Rooted Tree
Directed Graph
Layered Graph
License
Copyright 2019 Team-Blox
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.